Gus Potter

What happened to the Aberdeenshire project? I was rooting for you on that one. Now you're onto sand and granite.. help ma boab. Ok before you get carried away on drainage you need to look very carefully at where you are.. have you trucked over to the West Coast or moved a bit further into the Grampians? Quite a few of these sites (Islands & Grampians) have granite dykes with sand inclusions.. expensive if you don't know your way round the houses..a lot of the easy sites have been snapped up years ago. "I take it you know of glacial deposits that are stickier, but working with ground made of sand it is a new material to me." Yes I have a working knowledge but every day is a school day. "Yes, I learned about puddling re canal projects in the Midlands." Me too, cut my teeth on a project in the Midlands where a young couple had a canal boat building business and expanded to make a marina with a bit where folk could moor up all year round and live on thier barges. the marina bit had a lock and needed lined with clay.. happy memories! If you fancy post some stuff on your new site..to get best feedback you probably want to be a bit more site specific.. For all.. I think this is a great place to learn and exchange ideas but the folk that run it need some encouragement. That could be just a quick thanks to the mods or maybe a small contribution towards the cost of running this site? I'm more than happy to chip in with my contribution as I enjoy sharing what I know and learning from other members.

Good stuff. Do a good friendly informative report, you have the experience, take your contractors hat off and hold their hand, make it as easy for them as you can to check if they want. Yes, reference the proposed treatment plant. One key here is to make sure you say the plant is CE approved in the main body of the report..some tanks are still not CE marked so you can get caught out here.. leads back to the the Eurocodes which the Scottish Building Standard reference. The simple way is just to copy the manufactures data sheet and drawings as an appendix to your report. Then say " or similar and apporved" as this lets you select a different tank later if need be. Don't go over the score with the technical drawings.. better to include a few with your own reasoned analysis of how the tank will be installed on your site. Touch on the water table, potential flotation when getting emptied, the runs on the pipes to the tank, how you will empty it, the sampling chamber, DON'T forget to specify the manhole cover! light duty or heavy duty! It all sounds like a lot of work but you'll need to produce the same info for the builder, add a few notes and change the title box. You'll most likely sail through this but wrong spec for the cover and you are totally stuffed! Oh and are you leaning towards the pond idea yet?

Hello Old Kettle. In the spirit of BH and.. the planners.. we are all well intentioned folk. Totally agree we all need to live next to one another. To work this out you need to start from the outside plane of the roof and work back. It's generally accepted that the eaves height for PD is this. Project a line from the outside face of the wall up to the top side of say the roof tiles or roofing felt. This is the eaves height. The folk that drafted this are not daft! The wicked may add a lean to log store onto the side of their building. Here they (the wicked) would argue that the footprint of the walls complies with PD but the eaves height is say the facia level of the log store. The result would be that you could have a pretty high structure right next to your neighbours. Not very fair as they could do the same to you! The next thing is that the eaves height is normally measured from the natural lowest point of the ground adjacent to the proposed walls. Thus, if you have sloping ground it's measured from the lowest point of the established natural gound level. This to is reasonably well drafted. You get some folk that will "build up their garden" by adding decking or planters and measure from there. For the "enthusiastic reader of the PD rules" better to take your chances at William Hill. The planners have seen it all and now with google and all the histroric photos? Now you can dig down as what we are considering here is the impact it will have on your neighbours. If you sit the floor say 1.0 m below the existing natural ground level then the height for PD is still taken as that from the natural gound level. With a bit of thought you can probably get what you desire. If you are digging into the slope then you need to put a bit of thought into the SE / Geotechniques design as you are into maybe retaining wall terratory / damp proofing, maybe party wall stuff if not in Scotland. It's all a bit back to front but once you get your outside envelope established then you can work back without having to reappraise. Old kettle hope this helps.

You're doing a one off project in a fantastic part of the UK. Why put a big plastic tank in the ground! For me it sounds bonkers to put a plastic tank in the ground in Aberdeenshire just to comply with some fire reg. Save a Steading.. if you drive about you'll probably find that there are a few farms further up the hill that have clay and want rid of it or will deliver a few loads. Also, if you have loads of sand and gravel then a bit of clay introduced to the garden with the clay minerals associated will improve the soil.. all you need then is a few trailer loads of dung and hey ho..the cost of the pond will be mitigated! Remember that Aberdeenshire is in the rain shaddow of the Grampians and can get pretty dry. If this is the forever home then these things matter. Dig a pond and line it with clay! For all.. London clay was used to line dams! A well battered Scottish Glacial till will also suffice, it just needs to be a bit thicker. Oh, and once you get the Mallard ducks visiting they will do all lot of the maintenece and take care of the midge larve. For me if you have grandkids / kids then having your own pond allows you hang out with them, you can do the nature stuff but also teach then about water safety, what not to do and what you can do. When you can walk on ice and when you can't. Hey if the pond is big enough in Aberdeenshire you may be able to skate on it in the winter! Fish for tadpoles, what to feed the wild ducks... Mallards will nest in a duck house too on a small pond so long as they feel the foxes can't get to the nest. @the_r_sole "I would always rather put in the perfect application and get straight approval, but am wary of officials always wanting to show their authority by asking for more. " 'Sole.. that could be construed as just a box ticking excercise. Having read your posts I don't think that reflects the many years you have spent learning your craft and technical skills. I note you say you would prefer. Yes, there is alway the risk that we may encounter officialdom, it's something I wrestle with too.. do you design to just comply or do you challenge / stick to your design intent? Much depends on the Client.. but if you can say.. for all .. hey folks this is going to add value to your house.. no one else has this but do you want your dream home or do you want what YOU want.. Architecturally designed by the Sole say as a one off just for you.. what about putting the new Audi on hold for another year and spend your money on something that is going to deliver much more long term satisfaction and value. You can be cynical, chuck in a howler on your application with the full knowledge of your Client that the Authority will spot it and that you can compromise on, but still keep the design intent.. for me best just to stick to your guns and play it off a straight bat. What has happened to the system where we are even discussing compromising just to get approvals? Why can't designers / experienced builders / contractors use first principles to innovate? I think we can.. but we need to find a new way of communicating our ideas in a positive way that encourages the young folk that are on the Authority side to engage.

cyber attack! Yes they took a sore one on that but think they have recovered to most extent, but still feeling a bit wounded! Sole.. concur with the rest.

In the current climate I would do a good report.. Reports are often intended for a target audience as we know. Put together a report on your soakaway tests. I would aim for about 15 -20 pages. Include a site plan, an arial photo if you have one, introduction / conclusion to your scheme. Identify the objective.. tell them what you are going to tell them! Reference the head documents. BRE 365 for your rain water, septic tank percolation tests to say recommendations as per SEPA Regulatory method WAT-RM-04 for the septic tank for example.. the wee 300mm holes. Describe a bit of the local geology. Surface deposits and bed rock. You can find info here on this https://mapapps.bgs.ac.uk/geologyofbritain/home.html for your accademic research. Don't include a highly technical description of the soil, just say for example, river / glacial? deposits comprising SAND and gravel, or GRAVEL and sand. Then say what this means. For all the word in capitals mean that the soil is more composed of SAND. Don't lay it on thick just explain the reasons for the capital letters. Show dimensions to water courses and how the soakaway complies with boundary distance and proximity to the dwelling. If you have the will show a cross section of the ground. This can be helpfull. Put a note on the drawing saying for example X dimension complies with Y recommendation or clause 1.2.3. For all BH folk..if you have sloping ground what can happen is that rather than the water seeping into the ground and "going away" it just runs under the surface and appears as an unwanted spring further down the hill. Next for both surface water and spetic tanks tests and calcs. Plenty photos.. make sure you state the weather conditions leading up to the test and during. It is not unkown for folk to test at the end of a dry spell to get stuff over the line! Make sure the photos show virgin ground.. again it's not unkown for folk to cheat. BC know this and are wary of folk doing their own DIY porosity tests. Often I'll do an extra hole or two if I can if time permits. If you have good draining ground show that it is.. this can head any queries off at the pass. Now for the experienced you may wonder why I'm stating the obvious. At the moment some councils are in a bind, some less so but they are all struggling. For example one council I have dealt recently took nearly 8 weeks just to consider the information in the warrant application. I wrote to them and asked "how are you getting on" Got a very pleasant phone call from the senior BC officer saying.. we are a small council, half our staff have left and we are trying to recruit. Another council processed a warrant application faster than normal! It's worth producing a report that leads say a new BC recruit by the hand, write to give them confidence, give them pointers (SAND and gravel for example). They want to learn.. make your submission attractive, readable and friendly. For all the crusty BH members. Imagine it was one of your kids in a new job trying to learn the ropes. A good report should tell a storey and lead the reader..yes you can write a dry report, challenging and try an impress / bully with technical knowledge.. @saveasteading I would stick my soakaway report in with your warrant application. You won't get your completion certificate and probably your warrant until SEPA give you the OK. Best to get all this out the way early. In Scotland there is less of a worry about overloading BC with info, we don't have arms length BC or private BC in Scotland. But don't send them rubbish as this will hack them off. Having read your posts it looks like you have a very interesting project ahead of you. In an ideal world you may want to set this up so the Senior BC officer will feel comfortable sending a young trainee / or someone (older person) that is retraining to your site in the knowledge that you are not going to chew their head off. As you have a pile of experience you could build a good rappore with the BC officer going forward.. every one is a winner! Try and call SEPA and log the call.. but last time I called..they pretty much fobbed me off. I think it was because they are working from home and just can't shout over the office for advice from the seniors.

Yes you can mix and match. Yes there is a metal substitute for timber joists.. see Steadmans / Albion Sections for cold formed steel joists etc. You'll find these expensive as anything you buy will be a small order. Often you have to be more wary of condensation / humidity which does not fit well with musical instruments / sound production! Best to post some photos of what you have and a description of what you really want to do to get best feedback from BH. Sounds like an interesting thing with the added challenge of a limited budget.

The simple way, as you'll be needing a decent found for the two storey extension is to cast a small strip of found to extend the existing house found assuming it is strip found you have and not ground beams on piles say. Other things to just be wary of is things like ground gas.. does your house have measures to contend with this and the like? You can dowel this into the existing so long (good practice at least) as it appears to be just supporting the ground floor load. The foundation extension supports the new beam and block floor which can cantilever by up to say 75% of the beam depth to be safe if carrying a domestic floor load only. If you know what you want then find an SE who also knows a bit about design (they will give you free tips) and getting stuff through building regs. They do exist! A good experienced SE will have spent many years working with Architects, good experienced Architects have spent many years working with SE's... it's a two way street! In other words a good Architect can size up stuff structurally and not often be wrong! it's just that doing calcs for BC is not often their thing! Both if experienced will be well versed in how to do energy perfomance calcs, drainage design etc. Same applies to Building Surveyors, there are a few that are well rounded. I would shop about if you know what you want then you may be best with the SE / Surveyor route as you'll maybe get more "construction" information?

A pragmatic view from me..? Having built a few houses out in the sticks and lived in the sticks the last thing you want is for you house to completely burn down due to a lack of water if a fire occurs. Have experienced a neighbours hay lorry going on fire next to their house, used loads of water to stop it setting light to their house. The fire engine ran dry and we drew water from the ponds. If you have the room then ponds can be great fun, not just for kids to learn about nature but for adults too! Once you start to play with them.. it's addictive. If you have a descent roof area you can fill them pretty much with the roof and surface run off water. I can see the logic from my own experience about having a 45m^3 storage as but that is not a big pond. If you live up in say Aberdeenshire it gets pretty cold. If you are doing a pond then you want the aqua culture to thrive and not freeze in the winter. You can find plenty stuff in the SUDS manual about this but in essence you have a shallow sloping bit and a deep bit (1.5 - 2.0m) for winter conditions, lower light levels and so on. A pond of say 6 * 8 *average 1.0m deep will give you your 45m^3. It will vary a bit depending on evapouration so you need to do a few calcs. Yes if you are in sandy ground you'll have much loss so will need a plastic or clay liner. But all this needs to balanced against the fun you'll have playing about..the self build journey.. it's not all about the money you know!

And Great points, power to the elbow! The thing drew my attention to the stability was the aspect ratio of the structure. Height to windward length. In other words it is quite tall compared to it's footprint. There is also glass areas that would require some careful movement control not just in terms of vertical deflections but also horizontal deflections. Doing this in timber could be challenging when designing the connections to say the least! These types of TF connections need a lot of space which could destroy the Architectural intent. If you look at the the walls facing the wind in the east / west direction there are not many in the "right place" of a decent length (without some fancy modifications) to resist the wind loading in this direction. Now if we were to make the building footprint larger in the east / west direction but no taller it would be more "squat" when considering the east / west wind and probably have more internal walls we could use to brace. This would then concur with the order of your analysis. I agree that steel is not best suited to angles and curves.. in the round my feeling is that it is worth a close look at a steel frame on this project just to make sure you have not missed an opportunity. Beware modular timber suppliers quotng "excluding all steels". great advice from @saveasteading

@saveasteading You have hit the nail on the head here. You can use them as as part of the "treatment train" for water run off and pollution manangement as per the SUDS requirements. In lay terms. Green roofs can hold the water for a while during heavy rainfall and then release it slowly into the eventual water course.. helps mitigate flooding. Water evaporates too (when it stops raining locally) and so on so less ends up down steam.=adding to the flood volume. Also, during dry weather air pollutants settle and get trapped on the growing matter. If you have tin roof and a dry summer you get all sort's on the roof from bird droppings to particles from car exhausts. If you get a short sharp shower of rain this all ends up quickly in the river which probably has a low flow so the concentration of pollutant is high and it kills the fish for example. Green roofs can get you over the line for your permissions to build but saveasteading is right .. if you don't look after the roof, like you wash your windows or water your house plants it's all a load of.. guano / smoke and mirrors.

Hello Pipedream. Wow! No wonder you're happy! At first glance it may be worth looking carefully at whether this may be best build as a complete steel frame. The elephant in the room here is the global sideways stability of the building. On the ground floor you have a lot of glass, the building is U shaped, three storeys.. it will pick up a fair bit of wind load. I would get an SE to mull this over before you progress any further. Make sure you get the stability nutted out as you don't at first glance have enough walls in the right place to achieve it without some complex bracing systems and associated foundations to "ballast" it. This means money and a fair bit of it too! The above is not gloom and doom. You may find this is the most cost effective way. Steel is really versatile. For example you could look at a mixture of hot rolled steel beams ( the big I sections say) and cold rolled floor joists and roof members. They are often Cee shaped (zed shape on the roof) and thin walled.. just the same as you see in B&Q holding the cladding or an industrial mezzanine floor. Oh and you will probably easily carry any extra wieght of a green roof to boot. It requires a different approach (mind set) to the detailing in places.. cold bridging, insulation and fire protection but it's all doable. Cantilevers can often be more easily dealt with using steel, section depths are less and this allows you to more easily avoid "chunky" details and encourages more slender details for visual appearance. Really what you do is design an "industrial building" as the skeleton and over clad. The steel frame is just a meccano set, quick to erect. Also, many of the weather proofing details are already developed, you have less issues with shrinkage cf masonry and timber.. plenty positives. If you wish post more drawings. A good thing to do is put gridlines on the drawings if you can as it allows folk see at a glance how things line up between floors. Al the best with what looks like a great house.

Andy. No wonder this is causing grief. Here is a suggestion. Mull this over even if just to rule this idea out. It seems like you are getting run ragged. The following suggestion is based on tactics used to deal with say a home warranty provider who is using the fine print to avoid addressing the issues. Take a step back first. Get yourself a "street wise" Stuctural Enginneer. Get them to site for a day.. yes a day and expect to fork out £800.00 -1200 quid. Seems a lot but the SE will spend a few hours thinking time after they have left site.. not that bad. The SE will look to see where the frame is non compliant..and everything else that they can see or even if they "get a smell" they will look at that too. Once an SE is instructed to examine everything..it means anything else that may count as a contributing factor.. they do.. no prisoners! For example the SE will look at all the nail edge distances, plumbing of the frame, the roof trusses, the load paths and how this missalignment of the dormer may be changing the load paths and if the supporting walls are still ok. The ground levels, how the kit is sitting on the founds.. odd stuff that may not seem directly related to the issue.. damp proof membranes, vapour barriers.. tile batten spacing.. the lot! The reason for this is that all these other bit's an bobs contribute to what SE's call "robustness" and this forms part of the design codes. Also, if the say trusses are not sitting where they should be then questions get asked, for example are the connections still ok.. again are the tile batten spacings still compliant with the tile specifications.. it's a big can of worms to defend! Make no mistake if you are an SE and you are instructed to survey a timber frame.. well that is what you do! You don't muck about! The secret here is that once you find a non compliance that impacts on the structural safety of the building you have them over a barrel. What you then say is.. hey you may be quoting me the fine print but you have supplied / erected an unsafe structure. This cuts to the chase as if your SE say's it's not safe they have to do whatever it takes to fix it.. if it goes to court.. the SE stands up and says..they provided an unsafe structure and by that time the HSE will have been notified also, so too they will be chasing them. What I can say is that once you nail them on the structural side they are often keen to negotiate. The next step is up to you. You can try and negotiate a settlement yourself or you can instruct your SE to "have a chat" with your TF supplier. The SE will not "do a deal" on your behalf in terms of the fabric as professionaly they can't compromise on safety. The SE at this point acts as an independant person. To explain. An SE has a duty to public safety, you may sell the house but the liability rests with the SE long after you have gone. However, by acting independantly they will often use some back channels to reach encourage settlement that is equitable. They may for example say to the TF supplier.. well if you don't play ball with me I'm going to recommend to my Client that we get a QS of like mind to me.. no prisoners.. and the bill is going to go up. My Client just wants it sorted and quickly..they are not seeking to punish you but if you keep digging in they may take a different view! These are thing an advisor can say but you as a Client may not be so able to do. Andy. Quite often trusses may not be "quite where they should be" Not all of the trusses will be fully loaded so sometimes you only need to remediate a few, maybe one or two so it's not often a case of the whole lot needs to be taken down. The key here is to find the big stick to bring them to the table and quickly. The above is one possible way of achieving this. Ideally.. resolve it quickly, settle and not spend time trying to get your money after you have moved in. The moving in should be fun and if you have this hanging over your head it kind of spoils it? Lastly the supplier will also be expected to pay any SE fees you have incurred.

Jack. "It will never be commercial while I or any of the other people currently involved with the site are running it." Delighted to read this. Is there any merit in letting folk know what you need in funds + moral support + members own time to keep BH sustained? Yes BH have gone Ltd but I can understand what might drive that.. If you look back on the history of BH it seems to me like it started with a few enthusiasts all wanting to share knowledge. It caught on in a pretty big way. These founder members have put in a huge amount of work. I think to myself.. how is this to be sustained in the long term. It would be a sad loss if this body of knowledge and annecdotal evidence of folk building / renovating etc their own homes was to be lost. It is in fact a historical record! It would also be a disservice, not least, to some of the founder members that have been lost or just moved on if BH were to fall. Jack.. yes the advice on BH must have saved folk a fortune at times.. so 5% is a good ask! .. you won't get that quality of advice elsewhere for free. I ask.. how may we help?

@saveasteading Thanks for the "like".. I wrote it for you as I like the word "shifty" Just kidding. Gus

Mods.. I'm fairly new to BH, joined mid 2020. The resource seems to be expanding exponentially. This knowledge base is astounding. I think it is been so successful as you have stuck to the not for profit model. What are the plans for the future? How much more donations do you need to keep this running? How are you finding the time to run this site? saveasteading. Well articulated.

"Do you mean that a shifty supplier might have mixed nasty stuff in?" I do. "Otherwise, in what way have times changed?" Well I mentioned "happy days" Back then folk were not that daft, as are folk here are not too. In the happy days if someone had mixed broken asbestos sheets, fag packets, big lumps of bitumen, dead fish into the road planings, you will, even as a lay person be able to see it and say "hang on". But one thing that can be hidden is this. Generally modern bitumen planings are fairly benign. But up until the mid 1980's coal tar was used in roads and that contains a potential nasty mix of carcinogens that are more mobile. In other words they can leach more easily into your plot and start to contaminate your land. Now, when they are planing an old road they may take off the modern top layer (bitumen based), and a bit more.. the bit with the coal tar. So the top planings go to recycling, the last load (with the coal tar content) goes to you cheep. Back in the "happy days" we had little idea or knowledge about hydrocarbon pollution. "Have even used it under floor slabs, with BCO approval." Yes we did! For me if you have bought a plot or doing up you house why risk introducing an additional pollutant?

Yes at times. I do have a blog slot on BH but have neglected. Jeremy Harris, the mods et al have set a high bench mark! I joined BH as; it's not commercial, I find the folk here refreshing, there is humour, serious stuff where folk really need somewhere to turn to for help, great innovators.. the list goes on. I learn something new each time I look about on BH, it's a two way street for me and I enjoy being here. If there is interest from BH members in the structural side then I would give it a go and also post stuff on the blog bit so that it is all in the one place..but then it could start to loose the terms of reference of BH. In other words BH folk want to know about their own house / project and get a response to their own posts rather than read some generic stuff? I think this is the life blood of BH and why it works so well. Also, it's the Mods et al.. without their dedication, this site would not be what it is. Another thing is you have some real pro's on BH that have specialist skills. They may not post regularly, then in spurts, but the quality is exceptional. @SteamyTea "I would find it useful and save me having to find my copy of:"Why-Buildings-Fall-Down-Structures" For all. What about sticking to BH and finding out "what makes buildings stay UP"

If it's a public pedestrian path be careful as the Highway Dept may not accept as scalpings often don't comply with the plasticity requirements. Happy days when you could get road planings to do your drive to your new house or fill in a hole. Was great stuff. Times have changed. Think twice before you take up an an offer from a "road squad" who are doing a job "round the corner" and are offering a few loads of road planings for a few quid. It's not so much the bitumen content but the other contaminants that go with it! Do you really want this material on your property and the potential liability that comes with it.

Interesting stuff. "Our key driver is aesthetics." It's about 20 years ago that this cropped up for me the last time. We were talking about using concrete blockwork and brickwork in lime mortar to avoid having to introduce movement joints. Standard UK spec is say joints in concrete blockwork at 6.0 centres / brickwork at 9.0 m centres. We looked at lime mortar and as it was mostly concrete block decided not to take the plunge and spec it, knees got a bit wobbly! Fine on old stonework..but! But BadgerBadger.. hey, hand made bricks. There is a massive attraction here as you are maintaining the ethos. I commend you for that. Concrete blocks pretty much shrink over time and that's it. But clay bricks are arguably more lively and natural". They expand a fair bit in the heat, swell / shrink as the humidity changes and just move a bit as they age and weather. I'm not sure how this may stack up for you but if you have say a feature elevation of a decent length and going for the real deal with hand made bricks with a traditional clay mix then much will depend on you own personal desire. However, if you have a fair expanse of brickwork having a movement joint visible kind of defeats the purpose? And that drives you towards a soft flexible lime mortar which could do some 12 - 15m run? that much? without a joint or return corner to relieve the stresses? The other thing is whether you have a timber frame on the inside or are using a cavity masonry wall. If you're doing this then the regs on venting TF cavities could be a "damper" but with cavity masonry construction maybe easier to deal with? There is no doubt that it will cost you more but if you are going to do, it do it right and enjoy. Some folk buy paintings others build walls and get to see them every time they get home and walk in the front door. I would make sure that you don't get hung up on some building regs that require you to put in say plastic cavity vents. Solum vents would be ok as you could really go to town and get authentic reclaimed vents! Now I've just spent all your money!

Hi Tank. This is kind of for all and I can see it's a shed. I'm assuming that you are talking about a concrete lintel. There are two generic types. One is a non composite lintel. This acts just like a steel beam which is often designed to carry all the load on it's own. The other type of lintel is called a composite lintel. These lintels have a declared capacity based on the fact that they have brickwork that is laid directly on top of the lintel and forms a bond with the top of the lintel. In other words the brickwork is "stuck" to the top of the lintel and thus the lintel and the brickwork form a quasi arch.. work together to carry the load.. hence the term composite. Again, for all if you stick in a cavity tray you create a slip plane so destroy the composite action. Tank.. Based on your rafter size it looks like the lintel is not carrying a lot of load. If you have a non composite lintel then reducing the courses above should be ok.

Hello kiwibloke. "How does building construction type ( brick, block work, timber frame etc) affect the foundation cost?" Not that much on standard strip foundations. To provide some context. A typical two storey house with well propotioned load bearing internal wall loads a strip found by about 40 - 50 kN/m, a bit less if TF. That is about 4 -5 tonnes per metre run of found. A common allowable soil bearing capacity, say a consolidated clay (not soft clays) is 100kN/m^2 .. 10 tonnes per square metre. Thus a 600mm wide strip found can carry 100 kN * 0.6 = 60 kN per metre run = 6 tonnes per meter run so gas in the tank there.. Practically you often need a 600mm wide found to fit the wall on anyway and to give the brickie / ground worker a bit of tolerance. "My second question is what dominates the foundation cost, is it the ground geology or the building construction type?" For most domestic stuff it's the "geology" that tends to govern. Type of generic soil type ; sands / clays/ rock, chalks filled ground. Next you drive down; water levels, proximity of trees, ground gas potential and so on. "For the sake of argument If I am free to choose the geology and construction type what would be the best geology and construction type to minimise foundation cost?" Kiwi.. is this the Xmas wish list? Worked on a job a few years back. Top soil about 250/ 350mm thick from memory, great top soil all saved for the garden. A sub soil, clay / sand firm but easily dug and this was used to regrade the landscape. Then about three feet down (900mm) fractured weathered rock. This rock had not seem the light of day since the last mini ice age. Although fractured was great to support a house found. The site was slightly sloping and the rock was sufficiently fractured that we got good soakaway results for the septic tank and rain water run off. We excavated out the big hole for the septic tank with a JCB 3CX. We just carried on digging out the fractured rock here an there and used this as sub base for all the drive / hard standings.. saved a fortune. That was nearly perfect! Aye Conor you were lucky there! For all. If you are new to building a house think twice before you do your investigation with a mini digger. Also, if you have say one house under your belt.. well pride comes before a fall if you think you are suddenly a ground expert. It's often false economy. For a standard house set of trial pitting budget on something like a JCB 3CX for a day with a good driver. Get the SE to attend on the same day. Let the SE and the driver work together, stand back and just watch! you'll be amazed at what they can find and deduce! Make them tea and provide some buns and they will often include you in the process. It can be a day well spent and you can look back knowing that you have a good understanding of why your house "stays up". Take a standard strip found at say 900mm deep. To do a proper job you want to dig down some 2.7m or until refusal to be sure. If you hit something solid with a mini digger at say 1.5 m how do you know it is not a boulder! a mini digger is like taking a knife to a gun fight! A mini digger just does not have the "poke" and you end up disturbing the soil so much that the SE is left up with mince. What can often happen here is that you end up with an over designed found which will cost you a lot more than the extra expense of getting the right machine. "grabbing a handful of soil" Yes at times it may appear so. But there is a little more to it than that. I wonder.. you often pay your lawyer / solicitor a good fee without quibble, but balk when you need to pay say an Architect / Professional Contractor, Heating Engineer / Electrician for advice that will save you loads of money! Even though they are still all insured to the same if not a higher level!

Hello GlanMenai. You're off to a good start with your questions and research. Hope this helps a bit. To progress.. it's a good time to seek some professional advice. This could be from an experienced Architect (basements) or a specialist basement contractor if you have some contacts. Most often an SE is the best place to start as you'll need them anyway at some point so best to get them in early. I'm assuming you have an idea of what you want to achieve layout wise so this is more of a "structural" undertaking as you have a defined footprint. Most SE's say follow a process which is akin to this... 1/ Introduction.. meet.. discuss what you want to achieve, your "soft requirements".. warmth, light , bathrooms (this is to get a handle on drainage) and so on. You may want to create a lighwell outside to introduce natural light into a basement and this will involve making a hole in the outside wall 2/ Walk round the outside and examine the condition of the visible structure.. looking for and at; the topgraphy of the site (sloping or flattish), cracking, settlement, walls out of plumb, type of construction.. long list. 3/ Examine the roof layout and condition.. chimney locations and other features that could be heavy or become potentially unstable if some movement occurs when messing about forming the basement. Understand where the roof loads appear to be supported from the outside. 4/ Next go inside and up into the attic. Look at how the roof is formed and if the loads are evenly spread or are there for example large purlins transferring load to the walls in certain locations. Look for movement where the roof timbers join together. Often this can give an indication of how a building has settled over time as you can see how the joints may have separated / cracked over time. You compare what you can see inside with what you have seen outside. 5/ I'll assume the building is two storeys. Go to the first floor and determine which walls are the spine walls..usually brick. These are the walls that help tie the outside walls together, help resist the wind loading pushing the building sideways and maybe provide a bit of stability to walls containing chimney flues that need a "bit of extra help" to stop them moving sideways. It's also important to look for walls that may have been removed to enable a change in layout of the first floor. If the original layout has changed this is material as you may have lost a bit of stablity and tying for example. 6/ Go down to the ground floor and do the same. Here you often find that folk have been widening out openings in walls, putting in beams and this introduces point loadings which were not there when the house was built. All the time looking for signs of movement and "odd stuff" 7/ Lastly look under the ground floor. Look at in particular the areas where you think there may be point loading (that is why you start at the top and work down) examine the condition of; the mortar / the bonding of the masonry/ the quality of the original workmanship. 8/ There are are few expert plumbers and sparks on BH who know not to knock out large holes in the underbuilding..but often you find that a "cowboy" has smashed large holes in the underbuilding with a club hammer. In some cases you can see that the building is starting to protest but has not got to the point where this is visible in the living space. But one more "knock".. what then? 9/ Lastlyish examine the solum. Is it earth and what is it made up of? Can you see evidence of water rising, lots of salt deposits, signs of flooding.. again it's a long list. Now you have done your "Columbo" bit .. digest. GlanMenai.. you have gathered some info on the founds, well done. The next stage say for the SE is to have a look at the soil. Soil types are a massive subject so I'll leave out info on all the different types, already in this post folk are alluding to this and there is plenty on BH about clay / chalks / rock an so on and how they behave in different ways. To cut to the chase the SE will probably already know what generic soil type is likely prevelant in your area. A thing they will always be keen to determine is what the ground water conditions might be. This is fundamental to making head way as water can have a big impact on the capacity of some types of soil to resist load, remain structurally stable during construction (sometimes called stand up time and water management) when you are forming a basement (doing the work) and after completion. Clearly you need to know where the water goes as this will drive the design of the water proofing / drainage. Remember that insulation floats so you need to make sure you don't create a boat.. your floor could lift! Once you have gathered the above info you can then get to the exciting bit where you can explore the different insulation options, UF heating solutions and how much depth you need to fit it all in. It's stating the obvious but the deeper you go the more risk you run in certain types of ground. On the other hand there are some types of ground where you can pretty much dig to you hearts content.. within reason. Lastly, even if you are just intending to dig no lower than the level of the existing founds please get your proposals checked out. What you can do is remove what we call the "surcharge" which is the weight of the soil above foundation formation level. This apparently small weight can have a significant effect on the founds if removed, especially on old buildings that may have been mucked about with. Also, you can change the way the water drains under the house and in some cases this can result in unwanted movement. If you follow this process you should get a good understanding of how your house works and this could open up other avenues to explore that you may have not yet thought of! You may also save some money! All the best with the project.

It all look questionable. It looks like the columns and yet to be cast horizontal transfer beam are supposed to stop the extension swaying sideways. The right hand column has the rebar protruding.. as though you are going to make a rigid connection to the "lintel" The rebar sticking out the top of the column on the left is short and won't work to form this rigid type connection if the columns and "lintel" are to behave like a portal frame. It may be that it has been designed so that the columns act as vertical cantilevers with the lintel just "resting" on top. In this case you will need some pretty "beafy" founds. I would get your SE out pronto to have a look.

Hello Jack. Yes they will be working to something along lines of the Canadian / American codes. I appreciate your incredulity ...why not just provide you with the info and allow you, the customer to take an informed view? There can be many reasons for them not adopting this approach. One might be that the rep is not allowed to step outwith their brief. Their job (the rep) is to sell. The production manager and the folk that are doing the SE stuff in the background all have their positions to protect. That is part of modern coporate life, the greasy pole. It is not good for the "team" if the rep gives you the technical spec that say drops the production manager in the..custard.