TBlew

R Wall have been good so far. We haven't started to build yet, we will hopefully in the new year but have just had our xps delivery. They've been helpful in the process so far and it was good being able to visit a local build in process. Matt was really good at talking us through the process and answered all our questions we had both there and over email.

Thanks for all your comments. Very helpful for the waste in the slab. Still undecided for the floor finish. Everyone keeps telling me that I need to put a screed over the slab but this seems stupid. Does anyone have and door threshold details that they could share? In particular, we would like to have a fairly smooth transition from inside to out through our bi fold. If we want to use the slab as finished floor, or a small floor make up (an uncoupling membrane and tiles for example) how would the external doors sit with the slab? Do then sit on the concrete or on the insulation? Your responses are much appreciated

Yes we are using R-wall. We managed to see a build close to where we lived. I originally planned to use durisol, then isotex, but decided to go with more 'traditional icf' based on my structural engineers recommendations.

Thanks all for your comments and advice. Although we weren't after a premium glossed polished concrete floor, more a dulled down grey finish rather than exposed aggregate. There seems to be a lot more reasons not to go down this route. After speaking with my structural engineer and they resonated your comments regarding environment for curing, cracking, bracing etc. I am still keen to put the UFH into the structural slab as this will be the main thermal mass of the house and feel into the concrete of the walls. We are now thinking large tiles downstairs would be the way to go. Does anyone know what the best practice is for the bathroom plumbing is in a concrete slab? Mainly the shower trap as we would like to have a wet room shower on the ground floor. Would it be a case of getting the drainage in as best we can the cutting out the concrete to sink the shower trap down and connect into the pipework set in the slab? Struggling to find details of this in an insulated slab.

Thanks for the info. Not so keen on exposing all the aggregates. From speaking with a company about the finish, it would need to be power floated and then polished rather than a full grind. Then 2/3 layers of penetrating sealer. They've suggested minimum 100mm concrete to be able to polish it. Seems like a lot of extra costs for a second floor. Is it highly likely that you will get cracks all over the floor even with expansion joints? What do you mean by kitchen spec? Just having a perfectly level finished slab?

We have a south facing roof on our detached garage that we are planning to utilize first, and then the rest split over the house as you have suggested. Just in talks with solar company for our arrangements etc. Thanks, yes something i have thought about, hoping to add a cooling unit to our MVHR system. Do you know how effective these are? External blinds/sun shades could be added if needed. Carrick, Mid Cornwall, North Coast

Hi, Just a quick introduction to myself and why I'm on here. My wife and I have just started a self build down in Cornwall. Using insulated raft, ICF wall construction with a SIP roof. Aiming for an efficient, air tight build with low running costs. That's the dream anyway. Lots to learn & get your head around. So I'm sure I will have lots of questions and will try to help as much as possible where I can. Our project is a barn type build, that we are trying to do as much as we can ourselves. We've already excavated the site, started our gabion basket retaining wall and had our first 2 utilities connected last weekend. Cheers!

Hi All, We are using an insulated raft foundation system with a 250mm concrete slab with mesh. We are going to install our UFH into this slab and will be building our walls with ICF using the same product as the foundations. I have seen people use this slab as their finished floor for the ground floor with a polished concrete finish. Has anyone done this that can offer some information? I am struggling to find any details for door frames/thresholds etc. as usually the internal floor height is above the cill/frame of the external doors. We also have steel columns with baseplates wider that our internal walls. These were drawn to be hidden under a floor screen or similar. However, it seems pointless putting another screed on top of a slab. Is there anyway to hide these baseplates? Image shows our slab make up and the steel column and baseplate under the 'finished floor' height. Thanks in advance!