Andy H

thats very kind

I attach price list I received from Polar wall yesterday. I got a sense they could be flexible on price. I spoke at length to the Company yesterday (Alan Wheeler) and apart from him obviously promoting his product picked up useful information that was generally applicable. The most interesting thing was that concrete doesnt need to include a water proof additive if it is made with 350kg of cement and a water: cement ratio of less than 0.45. With this spec it will be waterproof. He quoted an old BS 8007 standard. I have yet to verify this but if true would give me a saving as I was planning to use waterproof concrete in my below grade walls. Price list 2020-doc.pdf Price list PLUS 2020-doc.pdf

Logix is an American product, the distributor in the UK is Build Homes Better https://buildhomesbetter.co.uk/ whom are also the distributor for Isoquick the Insulated slab product. Lasst week I attended 2 x 2 hour web training sessions held by Logix America. They were very good covering all the main points most of which is relevant to other suppliers ICF blocks. I was able to get questions I had answered during the web session. Logix is sitting high on my list as ICF choice but I have not yet commited and am waiting on Covid restrictions lifting so I can get to a site to handle the product as recomended by @Chanmenie and others.

I am in the process of selecting my ICF supplier. I watched the video on the polarwall site. I thought it raised some interesting points to consider and am going to give it some further consideration. There claim that XPS is better than EPS needs to be questioned. I have previously done a bit of reading on the subject and whilst it may have more compresive strength, absorb water more slowly and a slightly better insulation value the compresive strength is not relevant in its use as an ICF block, it holds onto the water it absorbs more than eps(leading to lower R value) and tends to be a bit more expensive. You could check out this link for more information https://innovativebuildingmaterials.com/eps-insulation-vs-xps-insulation/ Like you I would be interested to hear any feedback from members who have used Polarwall. Have you had a quote or estimate from them?

Sorry my error you are correct Thermohouse is from Ireland. I was getting mixed up with Econekt in Scotland who supply Izodom from Poland (This was my most expensive quote) I found Thermohouse responded quickly to my calls and I attach a price sheet they sent me for their products. The price list is all priced in cost per meter squared. Whilst the prices look low there is a high distribution cost and I was quoted around £1500 for 110m2. Factoring in the distribution I found the total price similar to Nudura. 2020 Guide Rate .pdf

Thanks for the comments and clear diagrams. I will investigate this 1/3 , 2/3 split. Do you or any other member know if the issue of interstitial condensation goes away if wooden beams are not used within the roof structure? What package are you using to make your diagrams in? Kind regards Andy

I can't comment on the past but my interpretation of the current guidance is that it relates to the whole building.

Thanks Jack I'll do a search on "rough plastering". On the running services I was thinking about having them on the wall within some protective conduit if I went for the woodcrete. I am quite attracted to the idea of a more industrial look - I haven't progressed the thinking to find out if it fits within building regulations yet. I am still on the foundations, walls and roof investigation phase!

Yes you are quite accurate I have had around 14 Muck away trucks already! I decided against planning for cost and time delays and in any event wouldnt want a building in my garden that was much above 2.5m high as it would dominate the garden so I would have still had to dig down to get sufficient height.

Half way through I was beginning to think the same! I think we decided to do it because the tree surgeon said we wouldnt be able to do it.

The idea was for the beams themselves to be laid with the 1:40 slope. Your point on visual clutter is worthy of serious consideration, I have just been mathematical about it. Your comments have also got me thinking of whether my sloping beams may look odd to the eye. I am trying to work along passive house principles, hence the 200mm insulation. The foundation is going to be an insulated slab and the walls ICF. So far I cant work out how I avoid any thermal bridges at the wall/roof intersection, particularrly if I allow the beams (and roof)to extend out beyond the walls to to provide some cover for the windows from the mid summer sun Thank you for your comments. Andy

I can have a pitched roof but the ridge of the roof is still restricted to 2.5m as I am within 2m of neighbouring boundaries. My thinking is that a flat roof with a very slight decline from back to front to facilitate water run off would maximise internal space -but this is my first build so I am open to suggestions. Thanks Andy

I am going to self build and this is my first job. My intention is to wait for the lockdown to end and get onto one of the courses run by my chosen supplier. I would supplement this with 2 or 3 visits by the supplier at key points, including attendance for concrete pouring to act as further training / quality control. I am building a single storey structure with walls 3.25m high, 0.75m below ground and and 2.5m above ground with all of the window and door openings on one wall. All of the suppliers I have spoken to seem to think a single poor would be fine even though their technical specs indicate otherwise. I guess the technical specs are being conservative but I think I will follow the technical guides and go with 2 pours, the first being with waterproof concrete for the below ground wall. I am considering the use of woodcrete (but am not yet decided) because of the discussed lack of a need for bracing. I have noted the discussion on this earlier in the thread and would visit a build in progress to see the level of bracing required. My other reason for considering woodcrete is it introduces the possibility of not needing internal or external cladding. I am being sent a sample to which I could try sanding, varnishing or painting to see if it is attractive (to my eyes!) I noted in an earlier comment the tolerance of the woodcrete blocks not being good enough for providing smooth walls. I will need to investigate this. Kind regards Andy

I suspect it would work out cheaper if you are doing the job yourself and not factoring in a cost for your own labour. In addition if I have understood the properties of woodcrete correctly, it is more thermally conductive than EPS and so the woodcrete form itself acts as a themal bridge albeit at a very low level, as the woodcrete runs the whole way through the block.

Did you get a quote from AMVIC?

I found them helpful but expensive on a like for like basis when you factor in distribution cost from Poland, so they havent made my short list

I haven't sent architectural drawings but hand drawings on graph paper. At this point I haven't finalised the building dimensions and door and window openings though I am sufficiently close for getting indicative figures. I dont want to get an architect or structural engineer involved until I have concluded in my own mind what I intend to do as I could end up with multiple drawings, calculations and professional fees. I have been pretty thorough on making them comparable for the items you have listed. There can be quite a variation, particularrly in prop costs and delivery. The one thing I havent got a fix on is whether there is much difference between the eps and woodcrete in terms of rebar needed.

I am finding your comments helpful so would encourage you to continue.

Has anybody had experience of Jackon? I saw them at the NSBRC Centre in Swindon. The product looke good to the eye and they also have an insulated slab product. Somehow in my gathering quotes I have forgotton to include them. So far I have found the best price from Build Better Homes who supply Logix ICF forms. They are also the suppliers of Isoquick insulated slabs.

I had a useful conversation with a technical roofing expert from a company called Bauder https://www.bauder.co.uk/. The company focus on waterproofing systems for roofs and we spent at least half an hour discussing my options, mainly to with structural options of the roof which they themselves dont provide products for. Obviously there intention is that you hopefully use one of their products but he was not in the slightest bit pushy. He quickly followed up the call with relevant information including CAD detail drawings and technical details. He was open to me calling him again if I needed further help. A possible solution from the conversation is a 'single ply warm roof system' . The details are as follows: 1. Structural timber beams to span the 6m building depth with a built in fall of 1:40 to be left exposed leaving height within the building 2. Plywood 18mm on top of the beams 3. Air and Vapour control layer 2mm 4 Insulation layer 200mm (stuck rather than mechanically fixed to prevent fixings showing through plywood ceiling) U-Value 0.125 5 Single ply PVC water proofing membrane 2mm, quoted 35 year life This would give a depth of 22 cm which is better than I had hoped for which means less digging! I will be getting a quote for the installation of I need to confirm that leaving the wooden beams exposed and using the underside of the plywood to form my ceiling is compliant with building regulations, but my reading of them is that it would be OK.

You have to scroll up to see what I was expecting you to see - the culmination of alot of work to get the stump out.

Lucky you! I mistakingly thought you had a structure / part structure underground - mine will have to be a permenant fixture☹️

Being within a conservation area I needed to give notice to the planning department that I intended to remove the 2 trees that would allow me to make full use of the space at the bottom of the garden for my building. One of the trees was a lovely Ash tree but unfortunatley (for the tree and the enviroment) it was signicantly diseased with an almost hollow trunk at ground level, extending down to the routes that would at some time fall down (see picture of tree surgeon hiding inside the tree, once it was cut). This was fortunate for my build as the tree having a limited life span was likely to get permission to be removed. The second tree was a large bay leaf tree. I was waiting on 'tenderhooks' for 6 weeks before getting the go ahead to remove the trees. I was now under pressure to get the trees down and start excavating - at this stage I was optimistic that I would be able to get the foundations and walls up before winter set in! I hired a tree surgeon to take down the Ash tree but to save costs I took responsibility for dealing with disposal - a big bonfire of all the smaller branches and greenery - I have kept the bulk of the timber for future use in a wood stove - still have to work out how to get it dry! I decided with the help of friends to DIY this tree. We managed to take it down without any incidents but unlike the Ash tree it sat on the building plot and the stumps and roots needed to be removed. The tree surgeon offered to grind it out for £1000 and effectively said we would never get out with our digger, picks and shuffles. We decided to prove him wrong and a couple of days later we had it out ( see video). It took many more hours, periodically chipping away at it over subsequent weeks before we got it to a size we could get it out of the back garden, transported on the digger. Digging the hole was a long job we hired a 1.5 ton digger which we got down the side of the house by agreeing with the neighbour to take down some fencing, the payback being I'd put up new fencing which they were happy about. We initially wheel barrowed the earth out to the front to be taken away on grab lorries but it was really hot and tiring. After 5 muck away trucks (estimated 80 tonnes) we hired a mini digger which worked a treat, in all I think we had 14 muck away trucks with a peak of 3 in one day! Bay_leaf_removal.mp4

This link explains how to drain the garden https://www.jdpipes.co.uk/knowledge/land-drainage/basic-guide-to-land-drain.html. I think I will do this in addition to the drainage and sump pump around the foundation mentioned by @joe90

Thanks for the photos - are you in effect building french drains in the land surrounding the proposed building? A friend of mine suggested that I build a french drain system in my garden directing any rainwater from the garden ever getting around my building in the first place. It sounded like a good idea. I could try and do something similar at my neighbouring boundaries to restrict the rainwater running from their garden into the backfill around the building.