Gus Potter

I was wondering if the ground levels are the same all the way round the house? Say you get a bit of flooding / raised water table then will the solum not fill with water? Do you want to keep the solum space? Is it possible to put the insulation under the beams, put the dpc on top of the insulation and turn this up into the wall so that is the 150mm above ground level, above the theoretical splash point of the rain. Keep the beams on the warm side. Yes you may need a thicker screed, maybe not if you can raise the beams a bit? You would still need to "pocket" wrap the beam ends where they rest on the supporting underbuilding to keep the continuity of the DPM?

Tortuous times for BRI44. As a general comment Bri has gathered plenty evidence and working though the dispute process which is incredibly frustrating. I do think that BRI has a good chance of success as a lot of the evidence is overwhelming. At some point the builder will probably wake up, count their beans and come to the table with a view to mitigating their losses... which will likely be more than if they had engaged( meaningfully) earlier. If they don't it will probably get worse for them. It looks like there could be some structural safety issues here. If say the HSE were to get involved then the developer may have to answer to them also, and that is not cheep in terms of loss of reputation, just for example. Having the HSE take an investigative interest in your business / or you personally is an experience to be avoided. Food for thought if you were the developer that built BRi's house.

As slate is a natural material it does vary as you work through the quarry / mine face. Take say a traditional Welsh slate, it can be quite thin but hard wearing and durable and the proof is available to see. They can be made thin partly as the bed is more uniform, less subject to inclusions and so on. One key is to also look for a good slater that has been properly trained with plenty experience. They will cost you a bit more but if you buy a cheeper slate / poorer quality slate then they will sort out a lot of the obvious (and less obvious too) duff ones when they are grading the slates. All batches need graded by thickness. You put the thicker ones at the bottom, thinner at the top. I made a post before about grading and so on. They will also fix the slates properly so that you can get in to maintain the roof easily as time passes, tailing where required - tiny tails - say 10- 20mm or larger ones if you want the visual effect. With a good slater you can still get a good roof without paying top whack for the slates. Or you can get a "gold star roof" with top quality slates and a top quality slater.. but there is a bit more wallet damage, although it will last for many, many years and more after that! There is a difference in the traditional methods of fixing slates as you move round the country as this knowledge has been passed down the generations. Thus it's worth speaking to your local slater as well as looking at the big supplier's technical guidance.

Connor makes a good point about the noise being transmitted through the joists ( I'll call that flanking sound at risk of being pelted). Noise tranmission is quite technical. But say you have a 1960's semi with a party wall. Often you find the joists are built into the wall. You'll often find that between the joists there is a "soldier course" of brick.. the bricks are on end, hence the word "soldier" as opposed to being laid flat. Lift a couple of floor boards along the party wall and look at the pointing on the soldier course, you'll often find gaps here as they were harder to bed properly and that timber joists will have shrunk over time leaving a series of gaps. It will be the same on the neighbour's side. They did know about fire protection even in the 60's but you were allowed to have a few beers during the day on site then so no one really bothered. Make sure you fill any gaps in the soldier course to avoid disappointment. Also, when you have the boards up it a good opportunity to run some extra electrics.. just a thought.. If you want to stuff the joists next to the party wall with say rock wool etc as well then keep this away from electrical cables as they can heat up. I think there are other posts on buildhub about this.. search for Jeremy Harris and similar poster's etc.

Hi AG_YB Nothing wrong in taking insperation from others, after all that is sometimes / often how we all make progress. It's what you do next that is important for you. We all design stuff even if that means choosing the paint, wall paper, a new duvet. Some do it to make a living, some for fun and or for personal satisfaction. But (personally speaking) once something is built you tend to look back and think..I could have just done that bit a wee bit better, or that bit is a howler.. and (not you) if you have not made some of these yet then time is on the "howler's" side. Maybe go back the the Architect (who's design you love) and ask how much it would cost to tweak it just for you? Maybe look at the orientation of the house, the views, how the sun sets and rises, shaddows.. you can make a long list. Also, look at how you are actually going to really use the house once you have been in it for a couple of years and the novelty has worn off? It may cost less than you think? It does no harm to phone them up and just ask. It's ok to get inspiration as Peter W says, just don't rip off other folks stuff whole sale and don't copy their actual detailed drawings. Personally if someone is copying one of my concept designs then it's quite good to be "followed" .. it's the only time I get to be famous. It's a good point you make about seeing something and saying "yes" .. it's a gut feeling and worth trusting, just check your facts.. just for reassurance. There are a few alternatives in terms of the traditional Architect route. If you know what you want or even if you don't then there are other folk that are competant (experienced enough) to deliver what you need. Some are pretty talented and they can also bring a slightly different skill set to the process that may suit you, it's worth exploring... you're not being a cheepskate just sensible and thoughtful. As a point of there are also a number of folk about who started out as Structural Engineers that do the Architectural (creative) side of things and deal with the permissions and so on. The professions cross fertilize as Structural Engineering requires vision, creativity and "inventiveness" also. Design is fun, creative and rewarding. I know few Architect's who incorporate good structural design right at the concept stage as they really enjoy it, they know their stuff, just they can't bear to do the calculations and funnily enough there are a few SE's who "cross the tracks".. to the Architectural side but you get the calculations / SE design as part of the package. AG_YB all the best, try and have as much fun as you can as this will often offset the times that things get a bit stressful.

Enjoyed reading all your posts, very encouraging and refreshing. Thanks all.

Sometimes, if you have no sheeting (sarking / ply) on the top of the rafters then if the roof is fairly big you want to fix wind bracing to the underside of the rafters. If you have a roof that can say get some snow drift off a higher roof this inceases the load locally. To make this work you decrease the spacing of the trusses where the higher loads are. This way you keep the rafters the same depth and it makes it easier to fix the wind bracing as the underside of all the rafters are in the same plane.

Hello Bri. You asked me "Should I get my own surveyor out as there is a few local? " Consider this first. There is a process that developer's often follow once a dispute starts to get serious. They know that from time to time (when serious flaws are detected) often a domestic home owner will eventually engage their own professional representation, and they know that this will start to rack up your bill. They then start to communicate with your representative, in the full knowledge that you are having to foot the bill for this...the war of attrition bit. It is unlikely that they will offer to initially cover the cost for your representation, unless you get them bang to rights, even then you may need to resort to other means to recover all your costs and maybe some compensation..wishfull thinking.. but not unkown. Your representative will also look at how much you can afford and how much time you are willing to spend giving them the supplementary information and so on, such as the info you got on build hub. There is no free lunch here.. often no pro bono! It's pretty clear from the other posts that all is not as it should be. Bearing in mind that the "developer" that you are having trouble with may also be reading this. Here are a few points. As I understand the Developer sent an Engineer to have a look. Their Engineer will (hopefully) have been briefed to some extent as to the scope of what they are to look at... it's unlikely that the developer will have briefed the Engineer to look at the whole building holistically and conduct a full intrusive investigation, as they see fit. You summarise to some extent that you were told verbally.. "it won't fall down" or words to that effect. Before you start to spending your own money it's worth getting some clarification from the Developer's Engineer. Bear in mind here that they have a duty of care to the public so if you write to the Engineer and the developer directly they (the Engineer) should at least respond, even if it is just to say they have received your communcation. They (the Engineer) will probably mention confidentiality etc, but it is the acknowledgement that matters, you are establishing the chain of accountability. if they don't acknowledge then more fool them. As per my last post and to expand. Write and ask how they (the SE) have reached their conclusion that the building is structurally safe; given that there are indications that the workmanship has been shown to be poor in the places (say not compliant with the BS 8000 series of codes, Euro codes where applicable, manufacture's instructions and general good practice) that have been opened up. Ask initially; have they looked at the wall ties else where. Have they checked if the mortar is to soft / too strong elsewhere how do they know what is driving the cracking? Is mortar variation localised, or generally homogeonous. Is this mortar strength influencing the cracking? How do they know the building is not settling.. why have they ruled out precise levelling techniques to check for settlement, if so on what evidential basis. In general what evidence do they have that the walls are as per the original design intent. How do they know if the inner skin is not cracked too, are any shear ties over the inner inner skin joints (if any) intact and still functioning correctly for example.. hard to answer when it seems they have not investigated internally. How do they know how the building works structurally given that it seems to now differ from the original design.. even if they have building control record drawings. How are they confident that the "as built structure" is the same as the record drawings.. what steps did they take to check? How do they know if there are other unidentified horizontal DPCs that are not breaking the bond in the mortar bed elsewhere. Have they checked that the alterations to the roof are compatible with the original design intent. I could list more but the essence is to get the Engineer to provide written confirmation of what they have been instructed to look at and what they have not. What they have inspected and what they have not. Getting to the bottom of this is the starting point. Once you get a handle on this you can then progress to looking at the workmanship and the serviceability issues. In some ways the two go hand in hand, if the structure is not correct then that needs fixed and in doing so the serviceability issues can be resolved as you go. In other words, you want to make sure the building is safe, and in doing so you fix the other problems and concentrate the mind of the developer. It is harder to argue about structural safety rather than the insulation and so on as you can't compromise on safety. You may find that when you dig a bit their Engineer drops them like a hot potatoe! Then you ask why! In summary you have been at this a while, maybe spend a few more days, a week or two asking these questions. It may be that you get no response or some deflective answer. No matter, as it seems that you have a good bit of evidence and any answer that is not clear and concise can benefit too in the long run, although frustrating at the times. If you ask the questions and don't get a comprehensive response then you are perhaps in a stronger postion to recover your costs, not just the cost of your surveyor but the cost of an intrusive investigation. If you are going to do this then you must write to the developer and tell them you are doing this and give them the opportunity to attend etc. Also notify them that you will be seeking to recover your costs. If you get no response or some deflection then this should bolster your postion to the detriment of the developer.

Bri. I missed Peter's post. Hang fire with the legal stuff, the lender and so on, it's probably not as bad as you think although it's no fun at all. Yes, it's a nightmare but it's worth keeping things under your control. Loose that control and ask yourself if this is what you want. In some respects as they have made such a mess of things it's actually often easier to pin them down. You've got all the emails and photos. This is the time to keep a cool head, calm things down and be forensic. It may only take a week or so to set the cat.. Once you raise the safety issue in my exerience things can start to happen quite fast as you shove a lot of liability onto the developer / builder / Enginneer and this impacts on their policies etc (you can save the facebook stuff for later). They can also get a HSE notice against them.. they (developers) are not keen on that as it has an impact on their insurance premium for example. Or, if they are also doing public works it's not a good look. Hope things work out ok. I'm not in your neck of the woods and but if you want you can PM me or look me up and I'll give you a few pointers if I can.

Hello Bri. Sorry to see you are still having problems, I appreciate your frustration. I have a case on my books that is much like your own, although it's worse (and more expensive I think) if that is any reassurance.. your not alone. You may feel that this is a war of attrition and that they are grinding you down.. a bit at a time.. nothing looks like it is a proper and lasting repair. The other posts are spot on so thank all. When stuck a bit / hitting a brick wall one tactic I use is to look at the whole construction and how all the elements of the structure are supposed to interact with each other. The design codes require that a building should be "robust" for example. Masonry walls are designed so that each brick, block interacts and works with the other elements of the structure. Once you start to make numerous repairs the walls can loose their strength and the overall stability of the building can be compromised. Can I suggest that you go back to the SE and ask directly if they have considered the overall stability of the structure given the number of interventions / repairs / damage to the block / bricks by removing the render and so on. Ask about the masonry. The render has been stripped, the block / bricks in places have lost locally / extensively? some of their effective thickness. Many mortar joints have been raked out and repointed. Pointing does not have the same bond/ compression / adhesion as the original mortar bed that underpins the design values in the codes. What we need to know, is for example; is the building still capable of resisting wind loads and so on? Ask the Engineer to say what codes they are working to and how these codes account for the numerous repairs. Also ask if they can show if the manufacturer of the helifix bars has considered the overall structural stability ( how the floors are tied in and so on, does the stability rely on the inner leaf only or both the outer and inner walls? ) if not who has. Have they also considered where the cavity trays / dpc's are and the possible associated loss of bond. If you get a reasoned justification with references to the relevant clauses of the codes backed up with the manufacture's data and your case review (which accounts for the recent interventions) then please post these here as this would be informative. We start out by designing a safe structure to say the original designer's requirements. What you can/should do as part of the remedial works design package is to review and check that any repairs are compatible with the original design intent before you embark on the works. Much of the issues you point out are what are called "serviceability issues" .. sorry to be blunt. You don't like the cracks, bad workmanship on the finishes, leaks, draughts and so on but once you get to this stage many developers start to run rings round folk and kick the can down the road. Hence your thousands of emails. In their mind it's often just you moaning and they get can get entrenched in their view as they know it's really hard to argue your point if you are a lay person. You can make a case on serviceability but it can be hard, like chasing cats. Turn this into a safety issue and in particular a public safety issue. Any SE (Engineer) will become very focused. Any confined brief they may have been given by a developer (developer's do this to keep the cost down), and any caveat they (the Enginner) will have put on their brief (you don't see that) will be binned as all SE's, Civil and other Engineers have a statutory duty to consider public safety. Your on your way then to getting some straight answers. Also, if it is a safety issue then this is a matter for the HSE! You can find that if you can pin them down on the structure and get them moving then rest can start to fall into place. It may need more extensive work / surgery but at least you'll be more confident that all is good. Bear in mind that the developer has been undertaking remedial works so they are responsible for the structural stability as they have, it seems, been instructing the remedial works and been responsible for these. See the CDM regulations and also ask if they have carried out a design review that has been passed to the SE who came to see you. If not, did they ask the SE to carry out a design review. The developer can have the rug pulled from under their feet as they should be able to show that what they have done is equal or equivalent to the design codes and followed the CDM regulations which include for making an adequate allowance for paying an SE for example who will consider the overall safety of the works. What I'm saying here is look at the whole picture, not the one the developer wants you to look at, this is how some developers close people down. If you can lift the bonnet then you can open up other avenues such as compensation /offset and so on.. for another day. You maybe can test run a two track approach, carry on doing what you are doing but open up another front, focus on the structural safety / stability aspect, ask the questions and let the developer pay for and show that SE has been properly instructed and that the CDM regulations have been complied with. If you do adopt this appoach then be careful not to burn your boat! Be canny, just ask questions and request justification as a lay person. I can be (has worked for me) that if you can nail them on a structural point then they need to remediate the structure and in doing so the other issues (insulation etc) are fixed anyway as all the work has to be compliant... You can then decide how to progress. All the best. Oh and please can all excuse my grammer /typos etc. Thanks all in advance

What a good idea. One thing that springs to mind is that you want to make sure you account for any drainage system, tanking or whatever so that any water penetrating the garden wall does not get into the house envelope. I've been toying with experimenting on my own house with something that will just emit heat in the evening, all be it a tiny amount. I dawned on me that if you can get the sun into the sunken part for part of the day then you can use the wall that gets the sun as thermal storage, so at night you get a little heat on your back and it may help keep some frost at bay for any plants. But with ICF maybe you can cast the walls, then strip off the insulation on the inside from the wall that gets the sun, render this, or scabble, or render with a pigment. If you paint it a darker colour /pigment the render then it willl pick up more energy from the sun. Is it much like the idea of a victorian walled garden? But here the heat escapes from both sides. But with ICF it's insulated from the cooler ground on the back side so all the stored energy comes out the right side. I don't know how hard it would be to strip the ICF from one side after installation? Or if it would just be a mess!

The sole makes some good points.. I agree that mileage with Engineers may vary..some provide a good service others less so, some provide more details, others less. I can understand why the Sole makes the point that the positives I made of looking at alternatives to the SER scheme are not the Sole's current experience. Different councils operate in different ways, for example Argyll and Bute often contract out all submitted calculations for review to local SER Engineers. I'll not dwell on this too much but the SER scheme was intitially set up with all the best intentions, however one could now ask if it has in some ways lost it's way, particularly with respect to the domestic, small works type of job. The sole makes a point of having received panel drawings.. There are generic panel drawings (cut and paste), and there are the real ones that a local joiner can work to, there is a world of difference between the two. Generic ones can be produced in a morning.. with a bun and a coffee, proper working and annotated drawings take a few days to produce.. the sheeting layout, the cutting list, practical guidance notes to the builder and so on, and most importantly; the tricky joint details, interface with the insulation details and so on..and integrate this with the Architect's design. It is these finer points that stop your house from falling down! You'll see some other quotes that state.. ".. on the basis that a competant contractor will develop the detailed design and adjust on site etc " and so on.. what are you actually paying for? The Sole sums this up in that the SER Engineer "confirms the design is compliant" ... in other words is conducting to some extent an audit process. If you submit calculations to BC then do they not check these for compliance? My experience is that they do.. but you don't get the smallish SER discount on the warrant fee. Yes, you get a discount on the warrant fee, it's often not that much compared with the savings you can make by having your own comprehensive set of drawings and calculations that you can use to tender to a local builder who will make the kit and supply all the insulation etc that you need, with the cost of each material item presented in a transparent way if you press for this. Yes, an SER certificate can sometimes speed up the process, much depends on where you are.. in fact doing it the "old school way" ..calculations + comprehensive drawings submitted to BC with no SER certificate can be faster than the SER route!.. my experience. It's interesting to see how the Sole notes that the SER process has become more "stringent". My feedback today from a local BC officer is that this is " partly to do with the audit process.. too many cooks" at the SER Ltd rather than a "quality issue". To get the best bang for your buck it's worth exploring all the alternatives, tried and accepted "traditional route" and the SER route. If your designer indicates that you have use an SER Engineer then ask about at other options before you commit to the SER route. You can get warrants through Argyll and Bute without an SER, yes it may take a bit longer but you can make significant savings depending on how you want to set things up. In summary, consider what is best suited to your method of construction, programme and tailored to how much you want to do yourself.

Lots of good points here. Miri Piri.. good points. You'll get there faster than you think.. break the task down into pieces, if your not sure about something then leave it and look at something else.. look at the finishes.. exciting stuff.. sleep on it. It's confusing at first but you are putting the work into it and suddenly it will all come together for you. Every day is a school day and I think we are all born stupid. In terms of designers..competancy, vision etc is a key and a prerequisite.. but it is your project. It's essential that you actually like the person, not all with agree with me but.. This is your home (not a commercial project) and if you don't take to them in the first few minutes then carry on looking, no matter how good the cv looks, trust your gut feeling and this will serve you well. No matter what you read about contracts etc, this is also a people business too.. your journey should be fun and rewarding and strangely builders are human too and like working for good folk who will give and take. If things start to get a bit rough then you need folk that like each other and this make it easier to sort things out. On big project's, HS2 say every one knows that there are no friends in the desert at the first meeting. You'll read lots of stuff about being hard nosed but it's not always the case..just be firm and fair, make sure you pay on time for a fair days work and there are a lot of builders who will return the favour!

Sounds like you are on track for a great house. Have a good look at your building warrant drawings and see how comprehensive they are. Maybe you have gone down the SER route so worth a good look at what you have to work with. Keep posting and you'll get a lot of help here, you soon be confident on getting the "hands on"..better for the wallet / purse etc and you'll have a lot of fun / reward in the process. All the best.

Thank you for you post Carrerahill. Very refreshing. The SER (Ltd) scheme is worth a bit more scrutiny, in particular in relation to the self build / house extension market in Scotland. I also appreciate the R_Sole's contribution, both Carrerahill and the Sole make good points. Broadly speaking there are two approaches to this..and it's partly about the money. Here is a bit of a summary. 1/ Much depends on what council area you are in.. if you submit calculations instead of an SER (Ltd) certificate building control will either get their own in house Enginneers to check the calcs or contract it out.. often to the same set of SER Engineers! When you prepare calculations (old school) you present them in the same format that the SER Engineers use. An SER Engineer should be doing the same amount of work, calculations, checking stability and so on as someone who is not SER registered. If not why not? Are other Enginners from Wales, England, France etc less capable / dilligent. Carrerahill perhaps alludes to this. 2/ It's horses for courses. If you look carefully at some of the SER quotes that have been posted on this site they are a bit vague. What are you actually getting for you money? Dig a bit deeper and you'll see that a lot of it is an audit process. There are two schools of thought here. The SER scheme makes much of how their members are highly experienced, this is true and for large projects you may want an SER member just to get it over the line in Scotland. But for a self build, extension etc you have an alternative. Consider the traditional route, as accepted in the rest of the UK. You'll also find that the "old school" folk also talk to the council Engineers on a regular basis as the council Engineers use this as part of their CPD and this gives weight to Carrera's point that the process in certain council areas is often not slowed down significantly. You BC officer, along with the council's Engineers will require a detailed set of drawings and calculations from the Engineer. Yes, this may cost you more on appearance but these drawings along with a good specification can form the basis of your contract with the builder, your SER certificate is of less use. This is where you will realise savings unless you pay your Architect to produce a full set of contract / construction drawings, specification and so on. But when you combine (coordinate) a good set of Engineer's drawings with the Architect's drawings (and they work closely together) it can be a good package which can save you money. Also ask, is it beneficial to have an independant check made by the council Enginneers who have no commercial interest. If an SER certificate is presented then the council have to accept this, even if they have reservations. 3/ If you go down the traditional route your Engineer will often have a much more hands on approach and be on tap when you need them. They will for example produce the panel drawings for the timber frame as the council Engineers want to see these. This allows you to get a local joiner to build the kit so you don't need to go to a main stream manufacturer or you can make the kit yourself. There are other benefits in that the Engineer will work often work much more closely with you and your Architect to make sure the structure really fits in with the vision. Yes, you need to pay apparently more up front. But ask this.. if you go to a main stream kit manufacture say, they have their own in house designers and they need to be paid too. That cost is hidden in the kit price for example. In summary, it's worth exploring this more. Carrerahill and the Sole are both correct but much depends on how fast you want to go, how you want to go about it , your cost curve / programme and what you want to do yourself and so on. There are potentially big savings to be made by avoiding or at least comparing the option of the non SER route. I work with a few Architect's who embrace the "old school" i.e non SER route as it give them another option to present to their clients for consideration.

You'll still need a pump to activate to get the pressure though.

Good points from all, ta. Just a thought. It's worth at this stage having a look at the size of the tank you'll need.. water is heavy. Look ahead and see if this will impact on the structure, would look a bit odd on the roof but you could make a feature of it, if so what are the possible cost implications. If you are on a hill then you may be able to sit the tank above the house in the garden if you have enough slope and gravity feed it all?

Ah, thanks all..I'm not alone! yes reassuring, ta

Good points from all. Eandg.. a good place to start is to look at the NHBC guidelines on building near trees. You'll find this online. Good explanation and diagrams. Type into search engine "NHBC building near trees setion 4.2." This will give you a good start.. easy to read. Clay shrinks and swells and it does this in all directions, up and down and sideways too. Your Engineer seems to be excluding this and passing design responsibility back to the piling contactor who has at least picked up on this. Turning to your quotes.. for a lot of domestic applications ( well commercial too).. some piling contractors work on the premisn of "who dares wins" When you are designing piles you want to make sure that you are not driving though made ground / fill. If this moves it can drag the piles down too so you need to take this into account. Sounds like you don't have made ground so look on the bright side. If you want to post the calculations and results of any gound investigation.

Hello Gem77. Sorry to hear that things are not going smoothly at the moment. It might be worthwhile trying to seek out a Quantitity Surveyor who works up prices for local builders when they are tendering. I'm assuming you don't have a standard form of building contract, rather, that you have a contract that is written by the builder themselves, or some other form of non standard agreement. What you may look to do is to ascertain; the value of the work to date, whether the work that has been done complies with the drawings, if not what elements don't. Also look at what materials are on site, the value of these and whether they are the correct materials. Say you have some beams.. check the lengths, weights etc and that they will fit, insulation if any.. check the type / performance of any substitute type. To find a QS like this you may want to ask here or go back to your designer and ask them if they know of somebody local. This may be the hardest part... to find a QS who can help you. You may need to pay say £ 500 - £750 (depends on the size of the project though) for someone to do a rough appraisal. The main thing is that it will give you a better understanding of the true value of the work so far. Also, you'll get someone to lend you a friendly / supportive ear (well worth the money) and advise. QS's no doubt will be seeing more of this type of outcome so they may have the makings of a solution that works for you. Once you get a better handle on the money and values of work to date then you should be in a better postition to take a view. If you have a QS on tap they can often keep you right while sitting in the background to some extent. Another key point is to try and make sure the relationship you have with your builder does not break down completely, hard to do at times. A lot of QS's are quite good at weighing up the risks and to some extent they can act as an arbitor/ mediator, depends on who you can find. This can restore the relationship and bring a project back on track both in terms of programme and payment schedule. If this can't be done then at least you'll have an idea as to how much it will cost you to change horses before you decide to part company with your current builder. It may just a fact that the builder can't do the work for the price he quoted without a substantial loss (go bust) due to the extra cost for example of materials and complying with the COVID regulations. Other builders are probably in the same boat. Having a clear view as to the quality and value of the work to date is well worthwhile. All the best.

Petew W makes a good point, Frenchdrain is a good solid solution. To be safe just make sure you don't make it too deep. Say max depth to top of foundation. If you have clay soil the French drain could dry the clay out too much under the found, it will shrink and could cause movement. If you have a gravel / sandy type soil it could start to wash out the fine material thus reduce the capacity of the soil under the found to carry the weight of the wall. If you have a sloping site then you may only need a drain on the high side, you intercept the surface ground water there. Often you'll have new rain water drains with pipe bedding and this too acts as a French drain, sometimes when you don't want it to though. With a bit of thought you can get the right solution with a little extra cost, if any.

Hello why-aye With a 17m span you can do a cold rolled steel portal frame, but as your eaves height is 6.0m a colled rolled steel frame is not really feasible to make fly. Much of this is to do with the sway in the frame. So your hot rolled frame is probably the way to go. Yes, you can basically construct an industrial building, over clad the insulated panels on the outside, for aesthetics. You are then free to fit out the space and get the acoustics the way you want. The extra dead load (of the finishes) will add a bit to the frame size though. Just watch the deflection limits - that is partly how much the building will sway , ridge bend by etc. If you are installing "brittle finishes" such as leaded windows etc you may need to reduce the movement so these don't suffer. Normally a standard industrial storage, warehouse type buiding is designed for a column height horizontal movement of height / 100. So 6.0m tall = 60mm deflection at the eaves.. quite a lot for a leaded window, sensitive (brittle) finishes. I'll post more stuff if you want to follow up.

Interesting photographs. There is a saying that if something does not look right it probably isn't. So I think you're right to query. Get some professional advice if you are not getting this at the moment. From what I can from the few photo's see the excavation may not be safe. Setting aside the geometry - blockwork setting out, as others have touched on this. The photos show a line of trees close to the excavation, you have a big "dumpling" of soil left in the middle and thus it seems like you are not doing a basement? Also, there seems to be no reinforcement in the hollow block walls etc. So it looks like a deep underbuilding to some extent. What you have seems to suggest that someone has designed this to comply with the NHBC guidelines on foundations near trees, hence the depth of what looks like a strip foundation. The thing is that these are guidelines. The key here is to look at the layers of soil. Tree roots seek out nutrients and water, once they find that they follow that strata. Often, with a bit of pragmatism you can make a case for not going down so deep. You need to look at the layers of soil and see where the roots will go, then describe this and make the case for the correct foundation depth.. thus the most cost effective option. The photos show that the wall is pretty close in places to the edge of the excavation, so not much room for a "clay board etc - compressible / void forming type material" which in layman's terms is a piece of soft material that allows the ground to swell and shrink without applying significant pressure to the side of the wall. Your excavation has what looks like a good "stand up time" that roughly means that you can dig a hole and the excavation will stay stable for a certain amount of time before it starts to collapse into the hole. How you measure stand up time is based on geotechnics and experience. It looks from the photos that someone has made the right (lucky call) and just dug the hole wide enough to get the found in without propping - thus, with hind sight the stand up time (so far) has been enough to get the outer leaf of wall in before the soil moves..for now. However, it also looks to me that perhaps someone has dodged a bullet in that if an excavation that size collapses there could be a serious accident.. ? The thing to watch out for is that if the soil now moves the single outer skin will probably collapse with it. You may be on borrowed time. Be safe first and foremost. What you have is interesting, so if you can, post some drawings of what is required, also, if you have any structural calculations post these too. Would be interested to see how this all works. Look after yourself and others. Again get some professional advice as from what I can see the excavation may not be safe.. it will serve you well. Al the best.

All the best Paris22.

Been following this with interest. Lots of good points by all so thank you. Before you progress / spend too much time / get stressed have you talked to a local Builder / Architect / Water board who knows where the drainage runs. There may be a reason for not building out too far in that if you have to deal with a public sewer, then all this could be a mute point as it could cost you a fortune to build over a public drain? Sometimes it worth looking ahead to make sure your efforts are going to bear fruit at the end of the day.