jimmyharris80

Hi guys - Any views on this please? Would it be best to move to another board if not in the right place?

Hi all, We have our planning app in with the local authority at the moment, we are working with a timber frame co. to provide a design and build wind and watertight package. They don't offer a groundworks/civils package so we are looking at establishing requirements, with a view to appointing a structural/civil engineer shortly. We have a soil report already and the ground conditions are determined as firm silty clay, med shrinkibility. Bit of detail on the site (see topo detail & proposed dwelling/garage attached)and what we'll need to incorporate into the design: Foundations & B&B Ground Floor - TF co. will provide structural loadings once they've completed the design & BRs. post planning approval. Site is pretty flat so I'd hope foundations should be fairly standard in nature (multiple fingers crossed!). Storm Drainage - We are off grid, our existing bungalow discharges rainwater directly into a small stream that runs along the front of our land within our curtilidge or onto the driveway or surrounding garden, all very Heath Robinson! Foul drainage - Again, we are off grid, the existing bungalow has a cess pit that requires replacement. We are looking at a sewage treatment plant solution, general consensus seems to be something with minimal moving parts, an air blower type (Bio Pure, Condor, etc). Our understanding is we will need to get EA sign-off to discharge the treated water into the stream for this solution. Need to consider placement of the unit so that it is far enough away from the house. SUDS/Soakaways/Rainwater harvesting - Given we currently discharge rainwater directly into the stream and it's unlikely we'd get permission to continue doing so, we potentially need to look at viability of soakaways (given clay soil), SUDS or rainwater harvesting solutions to offer betterment, we'll need some advice here. So a fair amount that we need to package up, design and get the relevant permissions and approvals. Does anyone have a view on how best to go about approaching this and could anyone recommend a civil/structural engineer that could assist us with it? Is there anything I've missed above that we need to consider and design in? We are based in Hertfordshire, is someone local necessary given we already have a soil report or would you suggest local knowledge of soil conditions be significantly beneficial? Any help much appreciated.

Thanks for the feedback all, appreciate it, give us a fair bit to think about and continue to refine. We've put a fair bit of thought into how we'll use each space and when. Kitchen/diner/lounge is the main day space when all at home together, Snug is the kids room for when they want their own space to watch TV/game or spend time just with their mates as they grow older, lounge is the more cosy adult evening space. The study/office doubles as my wife's workshop for her interiors business and my wfh office so needs to be of a decent size to accommodate us both and all the stock she holds. The south/east elevation does have a public bridle way running across the front of our plot so we haven't been able to open this up as much as we'd like in order to keep things a little more private. The house is in an elevated position so not so easy to shield using planting/fencing That's helpful, thanks. I'll have a play around with the configurations in RoomSketcher to make that work, should be doable. In the latest iteration and floorplans above the windows are 460mm, 685mm, 910mm, 2485mm wide and 2100mm tall, which are designed to work with brick. I understood the opening calc to be height = n x (65+10)mm plus 10mm and width is n x (215+10) plus 10mm? Will take a look at the landing, the idea for this space was for it to house a 'library' and small seating area by the window, I like the idea of removing the cupboard to make that a vaulted to bring in a little more light to the hallway, so will explore that. We did consider a fireplace/woodburner but discounted it due to cost. We do also have the loft space where we could place an MVHR unit, accessed via the landing. For the plant room we'll need space to house HW Cylinder, UFH manifold, home automation, alarm, electrics. I'll plan out the sizes of each item and see whether the space is adequate. We are looking an re configuring the utility a little as not sure the current config gives us the space we need for units, WM & TD, may need to remove the window to free up space and just keep a glazed back door for light. Point taken! We have already shifted the front door to the right and included some storage at the side of the door and a small bench seat. We do have the option to pinch some more cupboard space from the snug and/or utility so will look at this also. I've just looked out in our current hallway and we seemingly need space for about 25 pairs of shoes and 15 jackets, that's before any guests turn up! Thanks, I like the vaulted suggestion to remove the cupboard and also bring more light into the downstairs hallway. No probs, glad to be of service! It's great to get other peoples views that have been here before.

Thanks Mr Punter & AliG, We did discuss another ensuite but it felt a bit excessive to have 4 bathrooms in a 4 bed house, the placement of the bathroom between and easily accessible from three bedrooms is an adequate solution here we feel. Noted on the trees, we'll ensure we don't pick anything too imposing or that's going to grow to a unreasonable height or width. Agreed on point 1 on the shower, we will look to tweak this. The front door we'd assumed was notional, we'll certainly be looking at a more modern design so will get them to tweak as part of planning app. For the stairs we were looking at open tread (something like the below), the in-laws have a piano that my wife has plans to put under the stairs! We can increase the size of the exisiting cupboard toward the living room door and put a bench seat between the living room and snug (kid's room) doorways, we do have a fair amount of space to play with in the hallway.

Missed off the site plan:

Hi again all, it's been a good few weeks and we've been through a few iterations since I last posted and I feel like we're pretty much there and have landed on a design and configuration that we're really happy with. A summary of the changes we've made: - Tidied up the windows to make them more consistent across all elevations - Switched out the kitchen slider for a large picture window (this elevation benefits from the best views to the rear garden) - Increased the downstairs hall space to remove the pinch point at the bottom of the stairs - Reconfigured the master suite walk-in wardrobe and access to bathroom - Reconfigured the utility/plant room to improve the amount of units that can be housed - Increased canopy size so it now covers the front door porch (this isn't obvious from the drawings) - Shaved c400mm from the back of the house as those rooms could accomodate it - Added solar to the standing seam roof (this is an area we are now looking at in terms of viability and whether we will need to install Solar PV to meet the revised SAP calcs under new BRs) - Updated material finiahes: Roof & East elevation - Standing Seam; Main house - Brick; Pop-out extensions - vertical larch/thermopine; Canopy - render - Various tweaks to window placements to even up elevations I think that just about covers it. We'll be looking to submit to planning shortly, just drafting the other supporting documents on materials, design and access. Interested to know peoples thoughts on the (almost) final design:

There will need to be a steel there for sure. We have discussed cladding that elevation in standing steel following it down from the roof instead of the brickwork as drawn, this will reduce the load and hopefully the amount of steel required to support.

Thanks Ferdinand - Wow, that veranda sounds huge! If you did things all again what would you do differently? Reduce number/size of windows, modified glazing? Or a combination of all/most of the solutions you mentioned above?

Hi Adsibob, Kids are currently 6 & 8, the idea was to create a separate space for them for now (for toys, tv and such) then a place for them and their mates as they get older (gaming, smooching and what not!) Plan was for the water tank to either go in the plant room, another option could be the cupboard on the landing, but thinking is to situate it as close to the ASHP as possible which will likely go on the NW or SW wall near the utility/plant. I agree the lounges and playroom are a bit of a luxury, we see the open plan area as the day to day and entertaining space, with the lounge and playroom more evening spaces, we are keen to have a separate areas for the kids as they grow older to give them a sense of privacy and a safe space for them at home. We both spend a lot of time in our existing study (me 3 days a week, mostly screen time) and my wife (2.5-3 days a week, non-screen work), work from home is a big part of our lives and is likely to be for the foreseeable so we wanted the room to have one of the better outlooks that our site provides.

Thanks all, looks like what you have on your island is down to personal preference, my wife is also a big fan of keeping the island clean so looks like we'll be keeping the hob and the sink off of it! We'll be piping into a sewage treatment plant so anything other that liquid down the plug is a no no unless we want a nasty shock down the line. As the doors will be to the plant room I don't envisage it being a highly used space or one we'll travel through with our hands full so a double door solution would work I think. @Ferdinand Overheating is something we are very much aware of, this was flagged up on our previous scheme due to the large SW glazed gable end. We will be looking to put in MVHR as well as an ASHP as we are off grid for mains gas. Is there any area of concern you see on this design in terms of overheating? The lounge with the two large picture windows on SE & SW elevations, the SE window is covered by a canopy, would that be enough shading or is overheating is this room still a risk do you think?

Thanks JohnMo, we were looking at steel, but do need to do some research on other materials and associated costs, we'll also have some flat roof sections to cover so need to factor this in. Not heard of Sarnafil before so thanks for that, will take a look.

Sink on an island is a definite no for me, it just becomes a dumping ground for dirty washing, hob I can see the appeal, but remain unconvinced!

Still undecided on this one. We like the idea of a clean island for food prep, seating, breakfast bar etc but I do get the appeal of putting the hob there. I think it's an easy switch to make when we get to kitchen design so one to mull over!

This was a consideration for us, however, one of the benefits of our plot are the views to the large rear garden from that elevation, we wanted to take advantage of those by placing the main living space and home office (the rooms we use most) to that elevation. Putting the utility there felt like a bit of a waste, although we do understand the appeal of having it adjacent to the kitchen.

Hi all, Thanks for your feedback, really appreciated. It's easy to think you've thought of most things, then sometimes you don't see the obvious! Moving front door - Good point, on reflection that does look like a pinch point, option here could be to move the front door 1.5m-2m to the right, then extend the canopy over the front door so it's covered, we could then shift to door to one side of the entrance and have a vestibule area with a cupboard to one side and lose the cupboard in the playroom, freeing up more space in there. The hallway may then be a little on the large size? Window hotch potch on North elevation - Will take a look at this and see if we can simplify, take on board the issue of heat loss. Ensuite upstairs - Thinking here was that with 3 x bathrooms already across two floors that would be adequate, 4 bathrooms in a 4 bed house feels excessive, a solution could be to jack and jill the upstairs family bathroom from one of the bedrooms, maybe removing the bath to make way? Large study - Main reason for this is that this space will house the wife's studio for her home interiors business (2m x 1m workbench, fabric & supplies storage, etc) as well as my home office so needs to be larger than your average study, the idea is that in future this room could be converted to a downstairs bedroom with adjacent bathroom if required. Playroom External door - Good point, will look to remove this as access out via the back door is pretty straight forward from this room. Two sets of sliders - Alternative here could be to mirror the upstairs master bed picture window downstairs, I think aesthetically that would improve and simplify the rear elevation. Utility & pocket doors - Will see if we can shift the plant room door to the right, this could give us more worktop space. We could reduce size and add a bit more space to the playroom by shifting that wall to the left a little, but there's potentially a fair bit going in this room, washing machine/tumble dryer, doggy bits and bobs, bench seating which was the main reason for the size. Landing size - The idea here was to incorporate storage and house a 'library' wall, hence the size, this window does offer nice views to the front of the property and mature trees so we liked the idea of perching here with a book! Walk in wardrobe - Will look at configuration options here to simplify and make furnishing a bit more straight forward. @Bozza External materials wise, we're thinking standard brickwork for the main dwelling (a fairly subtle multi blend), standing steel roof (possibly extending this down the SE elevation, vertical cladding for the pop outs and either standing steel/render for the canopy.

Hi all, We are a number of years into our self build journey and are still to put a spade in the ground. It’s been a long and somewhat frustrating journey to date due to a number of factors but we are still fully committed to the project, which will hopefully deliver us our family home for the next 10-20 years! Unfortunately we had to take the difficult decision to abort our previous approved design due to cost estimates coming in way way over budget following an in depth review with an independent QS. A combination of material price increases and a complex design meant we just couldn't get the numbers to work, and ultimately is was too risky to proceed. Having discussed at length with the various suppliers we engaged along the way, their view was that there was complexity at every level of the design from the ground works (retaining wall integrated into house, stepped foundations, multi-level, etc) to the roof structure (large cat slide roof, 2 x glazed gables, 4 x dormers, rooms in eaves, etc), you can view the original design here if you wish. We are now into design number three, working with an architectural technician to formulate a proposal that focuses a lot more on function than form as well as adopting a fabric first approach (this was a major oversight on our original design) and utilising timber frame. We like the modern barn style so are trying to keep the main part of the dwelling in that form, with additional elements added to provide a more of an open plan design as well as provide architectural features. We now have a design and floorplan that we are happy gives us the space we need, and I am interested to know the thoughts of other self-builders who have been here before. I believe we’ve considered in detail how we'll use each of the rooms and will transition within the space, but there may well be something we’ve missed along the way or failed to consider, any input or critique is very welcome. Many thanks in advance Front elevations: Rear elevations: Ground Floor floor plan: First floor floor plan: Plot:

Yes, good shout, thanks. East Herts doesn't have CIL in place from the research that I've done, I will categorically confirm this before we start as that would be one expensive mistake!

Yes, you're right we are keen to get going, but only when we are comfortable with the approach and the ultimate outcome. I can put up with a few months of delay but psychologically we really want to make a start this year with demo and groundworks. We also have the small matter of a bat survey that will need to be 'refreshed' if we go through another bat season, that survey was complete in last years season and found we had a single bat roosting in the original bungalow (don't get me started on that!), this doesn't impact our ability to demolish the garage to make way for the new build, but a considerable delay could potentially mean more expensive surveys. Ok, thanks, will pick up with the architect then and establish what required from them from a time and cost perspective. That's one positive! Fingers crossed we have a similar experience. Now my head is whirring as to whether there are any other simplifications/amendments we should take a look at in the overall design 😣

Thanks Conor. A whole new app or an amendment to existing, or is it only the planners who can advise on this really? Will do, as we have a slopping site I think we could lose a fair bit here by levelling that out but it could need some retaining walls (sleepers maybe) to help with this, I'll investigate if there are any other local options. The top soil we'll certainly use it's whether we can find a home for the silty clay underneath.

Thanks for the responses guys, pushing the retaining wall back does make sense, additional costs, yes, but these would be balanced by the simplification it brings and the increase in square m on the ground floor, cinema room, gym, plant room are options here (budget won't stretch to the former two, but can leave unfinished with that as an option in the future). Plant room in here also frees up space in the utility which was doubling as our plant room. We do have a large garden where we could lose some of the soil by landscaping and we will need to backfill the SE side elevation so we can reduce muckaway cost here. A level change in the kitchen/diner would remove the need for steps/handrails and will reduce the height of the bifolds and windows, both will bring costs savings (not huge, but savings nonetheless!). First floor can then have all timber joists throughout instead of mixed timber/concrete, whether this saves cost I'm not sure but certainly looks simpler from a design/build perspective. The next logical question here is the impact on our planning permission, I would hope the change in window/bi-fold sizes would be classed a non-material amendment, but building out the basement and increasing the sq m on the ground floor and adding access to the basement rooms from the hall/bedroom 1, would that require a new planning app? Fundamentally the super-structure remains as is in size and form so I would hope the planners would be sympathetic to that, but who knows with the planners, all a bit of a lottery. Here's what we have approved at present with my amendment overlays in yellow as I see them: Any views on planning implications? I can stick a post on the planning forum to garner opinion before I have an initial chat with architect, just conscious of starting too many concurrent threads!

Hi Bitpipe, Yes, we did get a topo survey done and this was passed to our architect. This is what I was afraid of, even to my untrained eye it looks complicated. We have discussed extending the basement as an option, just need to consider additional costs of muckaway, retaining walls and slab as we're doubling the size of it if we go down this route. The step down was to increase head height in the kitchen/diner, I don't feel foregoing this would be a huge issue, the 1st floor would all then be on the same level with a ceiling height throughout of 2575mm which I think would be workable. This is what MBC suggested as the way to go when I spoke with them, it would mean a passageway around the basement level and bridges to access the garden from the 1st floor, we're getting into fairly significant redesign territory here I fear!

Great shout, we are keen to move forward but only when we know what we're proposing is achievable within the constraints we have and the risks we're willing to carry. I'm starting to question whether the current design is doable within our budget, but I'll keep plugging away researching and informing myself as much as possible to establish this one way or another. I've put a post up on the foundations section for people to give their views on what the art of the possible is.

Here are the details of our soil tests: Site plan: Ground make-up: Test result from TH2:

Hi all, Recent joiner here looking for some advice on our foundations/retaining wall/semi-basement on our sloping site. Here’s a pic of our site, I’ve marked on it approx where the new dwelling will be sited: We have PP for a three story dwelling, the ground floor is less than half the area of the first floor, you can see a few design 3D’s on my intro post here of how the dwelling is situated on site and what we are proposing, here is a sectional diagram showing the split level: The architect has added notional B&B flooring on both floors for BRs, I think we need to look at slab for ground floor as we will have UFH throughout (we're off grid so ASHP in the plans), first floor could be a little more complex as approx. half of it is over ground that slopes away. I’m struggling to see how this will all hang together and want to be clear on possible options we have and requirements when I instruct our SE. We only envisaged excavating for the ground floor, building up retaining walls and ground floor in blockwork with timber frame from 1st floor up. If we excavated the whole house footprint there would be considerable additional muckaway, retaining walls, etc for what would effectively be a ground floor void with no light and reduced head height. Any input you guys have would be hugely appreciated, if there's any other info, floorplans, etc that would help please shout and I can add them up. Thanks

Thanks Bitpipe, very informative, when you put it like that is all sounds so simple! The more I read and begin to understand, the more I think there are elements we can manage ourselves and it's certainly becoming more appealing, just looking at the wealth of knowledge here and the assistance other self builders in our situation have received it certainly gives me more confidence. We know there will be a lot of decisions to make a long the way and there will be a lot of time required on our part, it's just the management side of it and dealing with the interfaces between trades and ordering/scheduling that we're a little nervous taking on ourselves because it's all new. Taking on some of the management will potentially elongate the timeline, but that's not necessarily an issue as we'll be living here on site in the current bungalow minus garage and a back bedroom which we'll need to demo to make way for the new build. Taking our time and getting it right is more important than speed, we plan to live in the place for 15-20 years. I had a chat with Keith at MBC yesterday on their slab system and his view was that having the retaining wall pushed back and separate to the slab was the way to go which then works with their slab. That is not what we have in the design, the retaining wall is incorporated into the structure. He did give us a contact of a groundworks firm he's worked with previously on a similar setup so I will look to make contact with him to get his view. I think I'll put a post up in the foundations section to cover this particular element, as it's a significant part of the build that we need to ensure we get right. Right, back to reading some more posts on here, it's what i'm doing in every spare moment I have!