AppleDown Posted Thursday at 22:19 Share Posted Thursday at 22:19 (edited) Looking at the cross-section we have from our Architectural Technician for our piled raft. Before I go back with questions - his inclusion of a 'pile' on the edge of the concrete makes it look like the timber frame is floating on nothing. Am I right in thinking the raft needs to extend under the timber frame wall and dwarf block wall, and then add some insulation outside of that? Also, what does the DPM do? Then you have the perimeter build up next? Or am I taking crazy pills? Edited Thursday at 22:21 by AppleDown Link to comment Share on other sites More sharing options...
nod Posted Friday at 08:20 Share Posted Friday at 08:20 The actual design will need to be done by a Structural Engineer Im not sure why the Architects would get involved with foundation design Not really there bag 1 Link to comment Share on other sites More sharing options...
IanR Posted Friday at 08:54 Share Posted Friday at 08:54 (edited) 10 hours ago, AppleDown said: Looking at the cross-section we have from our Architectural Technician for our piled raft. That's not a raft foundation. Is the technician calling it a raft, or is that an assumption you have made. Yes, to be a raft, what is shown currently as a concrete slab needs to extend under the load bearing walls. If you are after an insulated raft and require it to be supported with piles due to ground conditions, that's quite niche. You'll need someone with proven experience. I'd recommend having a chat with Advanced Foundation Technology: https://www.advancedfoundationtechnologylimited.co.uk/our-products/timber-steel-icf-framed-building-foundation/ Edited Friday at 08:54 by IanR 1 Link to comment Share on other sites More sharing options...
AppleDown Posted Friday at 08:57 Author Share Posted Friday at 08:57 32 minutes ago, nod said: The actual design will need to be done by a Structural Engineer Im not sure why the Architects would get involved with foundation design Not really there bag I totally understand the piles and slab will be designed by a SE who knows what they're doing (that's happening at the moment), but in the actual details of what's shown for the slab to wall junction, and how it's supported - are my assumptions correct? If the slab extends to under the upstand blocks, is that how it should look? And if so, what's the route of the DPM? Link to comment Share on other sites More sharing options...
saveasteading Posted Friday at 08:57 Share Posted Friday at 08:57 Worrying really. That drawing is pointless, as a proper expert needs to take over. You can see the issue so why can't your technician? The note should say " do not use this drawing". They dabble with mentioning eccentricity of the load. Who even says it needs piling? The choice of pile could change that whole design. Does the floor sit on ground, not piled? If you have a ground report can we see it? 1 Link to comment Share on other sites More sharing options...
AppleDown Posted Friday at 08:58 Author Share Posted Friday at 08:58 3 minutes ago, IanR said: That's not a raft foundation. Is the technician calling it a raft, or is that an assumption you have made. Yes, to be a raft, what is shown currently as a concrete slab needs to extend under the load bearing walls. If you are after an insulated raft and require it to be supported with pikes due to ground conditions, that's quite niche. You'll need someone with proven experience. I'd recommend having a chat with Advanced Foundation Technology: https://www.advancedfoundationtechnologylimited.co.uk/our-products/timber-steel-icf-framed-building-foundation/ Sorry, that's just me using the term - can call it slab. As above - if the slab extends to under the supporting dwarf wall upstand, is that then correct? Where does the DPM meander through? Link to comment Share on other sites More sharing options...
AppleDown Posted Friday at 09:01 Author Share Posted Friday at 09:01 Just now, saveasteading said: Worrying really. That drawing is pointless, as a proper expert needs to take over. You can see the issue so why can't your technician? The note should say " do not use this drawing". They dabble with mentioning eccentricity of the load. Who even says it needs piling? The choice of pile could change that whole design. Does the floor sit on ground, not piled? If you have a ground report can we see it? It definitely needs piles. GR has been sent off to about 10 different people - including AFT and Tanners, and all suggest it either needs replacing down to 2.5 metres with new ground, or piles. Piles is easier and cheaper. The design for loadings has been done, so they know where and what depth to place them at. I'm just trying to work out if that drawing makes any sense - as my understanding is based on what's on the forum and what an initial part-time PM is telling me. If the slab extends further, is that all that needs looking at - or are there other glaring mistakes? Link to comment Share on other sites More sharing options...
IanR Posted Friday at 09:10 Share Posted Friday at 09:10 (edited) 31 minutes ago, AppleDown said: Sorry, that's just me using the term - can call it slab. As above - if the slab extends to under the supporting dwarf wall upstand, is that then correct? Where does the DPM meander through? No, the insulated "slab" can't extend under and take the external wall loads (making it a raft) while sitting on PIR and without a suitable build up under the raft (see AFT examples at link I provided) What's missing in the AT's sketch is the pile capping/beam that joins the top of the piles for the dwarf wall to sit on. Giving the AT the benefit of the doubt, the rectangle they've drawn is intended to cover the piles and beams. What have you asked for with regards the floor/foundation. There appears an attempt to go above building regs regards insulation, but there are better ways of doing it. Edited Friday at 09:30 by IanR 1 Link to comment Share on other sites More sharing options...
ToughButterCup Posted Friday at 09:12 Share Posted Friday at 09:12 Just now, IanR said: ... What's missing in the AT's sketch is the pile capping/beam that joins the top of the piles for the dwarf wall to sit on. Giving the AT the benefit of the doubt, the rectangle they've drawn is intended to cover the piles and beams. .... Beat me to it Ian..... 1 Link to comment Share on other sites More sharing options...
Mr Punter Posted Friday at 11:04 Share Posted Friday at 11:04 What about piles and ground beams with beam and block floor? It may save time and money and it is widely used. Link to comment Share on other sites More sharing options...
saveasteading Posted Friday at 11:31 Share Posted Friday at 11:31 There are very likely much better ways to do this, but we are dabbling unless we know the site, the job, and see the ground report. @AppleDownsending to 10 people is wasting a lot of people's time or, they won't answer. You need a design expert who works for you. Your chosen SE should suffice for now. 1. Get the slab built 2 put a house on it. Link to comment Share on other sites More sharing options...
saveasteading Posted Friday at 11:33 Share Posted Friday at 11:33 27 minutes ago, Mr Punter said: piles and ground beams That's likely to be a good option. What size is the house? Link to comment Share on other sites More sharing options...
ToughButterCup Posted Friday at 15:13 Share Posted Friday at 15:13 A quick referral @AppleDown - Tanners (referred to above) may be in Eire, but they answered every question for us promptly. More to the point, they made just one sensible suggestion about piles which (together with colleagues on BH) saved us many thousands of pounds. 1 Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now