marmic

thanks all - walls already on..........not a common detail (bit belt and braces if anything - certainly won't have any damp!) but BC approved, structural warranty approved, and calcs bring us to passivhaus high performance. Larsen truss panels (which are mainly insulation!) have all the load on the 140mm. The 'outer' brickwork is just to look nice and hold the insulation & persicope vents! would have been nicer off a raft but had to be suspended. Original plan was preinsulated concrete planks which would have been a lot easier - but had to change after manufacturer moved the goalposts - dpm capability / level tolerance / required topping.

ah... not thinking - I'll 'post' my horizontal insulation in first today - it's here ready and waiting. Each with a decent bead of GP sealant. This solves the problem of overflow! But still need to decide what to put in the gaps tomorrow 🤔

thanks both for your thoughts. 6-7mm ish - zero between sole plate and dpc. Zero of course being the high point of coursing blocks. Just over 40m of soleplate - but gaps not all round thankfully. External horizontal insulation not in yet (arrowed green). This will be cut and sealed in with the required 10mm gap to larsen truss panels and closed off with compriband/similar. Cladding last. blue is dpc/dpm red air tight membrane lapped and sealed to walls and for screed

@janedevon may I ask please what was your conclusion was? - if you are still on here? if anyone happens to be reading this over their coffee and has found the easiest/best product and method to do this would appreciate some knowledge from experience please 🤞. Just been scouring 'screwstation and toolfix' websites and will continue looking once I've sent this - currently very undecided what to use as quite a selection it seems. Thought I'd put the question out there again but bit of a long shot as need to decide quick and pick something up shortly this morning! Can't be too runny of course as it won't fill the gap and will just pour out. Only possible to get to it from inside - but don't want it coming out the other side either - there is a gap there (larsen truss wall panels) which will be filled with extruded installation before cladding. The 'soleplate gap' is outside of the internal air tight layer. Need to get stuck in and completed before Monday (amongst other things) when dpm/floor insulation work etc commences. Non shrink grout is the official line from the timber frame manufacturers - with my skillsets probably needs to be in a cartridge or foil sausage to pump into small gaps (between DPC and sole plate) Their site install team (very experienced) have suggested however most people foam it (but stopped short of recommending). Right or wrong? Thermally better, easy, and will hold / fill gap no doubt and probably go further in. Low expansion foam I like the sound of for doing the job, but it's limited structurally of course. Any thoughts please? Packers are spaced as designed and level is within timber frame manufacturers stated [sta] tolerance - and they were happy when preconstruction check took place. Still small gaps of course Install team actually commented our base is probably in the top 5 for level tolerance of any project they've installed - from self build to large developers. But still doesn't make it perfect with gaps present, however small, anywhere lower than the highest points. From comments I've heard/read in various places it seems quite likely the truth is many soleplates probably end up being fixed out of level pinned down tight to whatever is there - not right either! No comments please about what should have been - yes we know! This isn't helpful! Couldn't have a raft/slab/power floated foundation etc due to soil conditions - would have been so much simpler! Unfortunately perfect groundworkers/brickies are like rocking horse #### it seems - and many think they know better. The company we used did lot's of things well but where they didn't (number of items) they didn't like being told! Levels for example they brazenly stated and argued were within tolerance on scope (fortunately I had the sense to state less than actual max), which they weren't, and clearly didn't like the fact I was capable of checking! Short of a blazing row (was very close) or worse, and/or a long winded expensive court case / delays to whole project etc there was nowhere to go really. If this was traditional masonry build it really would have been fine. In addtion to clearly not fully digesting written scope / drawings and detailed conversations also made extra work for himself (not me) by ignoring suggested sequence due to unusual site conditions (he knew better, or thought he did!). We came to a commercial agreement on items I agreed to put right (not enough in hindsight) and remedial works completed despite not enough hours in a day already! Looking at it optimistically however maybe the cost was lower than if we'd been able to find somebody who could have completed work to perfect exacting standards - but would we have been able to afford this, and could it have been done in time? - probably not based on other responses. Bottom line is we are progressing and all will be fine.....................not a complicated project thank fully... Maybe I'm over particular, but I know what i want/expect! The groundworks stage has put me off ever doing this again unless money was no object! I work in the construction industry anyway (for a manufacturer - not on the tools and not currently housing) so know the score and how things work - which is probably why some so called trades have been a bit reluctant to work on our project as they know I know! not a bad thing as probably helps sift out the dross! Have had 3 people actually now say 'you know too much'! So I can only assume there's a huge amount of poor workmanship still hidden out there in housing, big and small........ rant over!

oh and nails or screws - for batten and cladding? (for the sweet chestnut need to use stainless). trada etc recommend screws for cladding - but most suppliers so far seem to suggest ARS nails, and some supply too

Afternoon all, on the next topic now and need some more opinions please! Plenty of contradictory information out there including from various timber suppliers and 'official guidelines'. So to cut through the uncertainty - what's right, and what's sensible / acceptable? We have timber frame larsen truss wall panels with 38mm studs to fix battens to (through the breather). Plan all along has been to use 25x50 battens. We have full plans approval and I know 25mm cavity is fine. Cladding will be horizontal sweet chestnut (as discharged planning condition) and have narrowed down to feather edge or shiplap. Visaully feather edge probably preferable - but cost, practicalities, and speed all factors too. (Rebated feather edge or half lap out as I need to trust somebody to leave the right gaps - and after the groundworks phase would rather mitigate risk! And I don't have time to do myself as have to work for a living. Waney edge visually was top of list but is out due to increased thickness and corner detail dimensions and how this interfaces with eaves/verge) 1. We will have butt joints in the cladding - how many depending on cladding lengths. (shiplap available longer wth finger joints). The recommendations (tdca / trada / elsewhere) is double battens at joints. And in which instance battens should be min 50x38. But seems possibly to be more precautionary rather then necessary. If I keep to 50x25mm battens and if nail/screw holes predrilled (which is the plan anyway being hardwood) is a butt joint in practice ok here just over the 50mm? Feather edge if green maybe not so good as a machined/dry shiplap. Or just side fix additional batten 25mm thick and ignore 38mm? 2. I haven't checked with timber yards yet but when I worked in timber industry 50x38 simply wasn't a standard size batten. The next question is batten grades - been reading reference to cladding battens are necessary and roofing battens shouldn't be used. This a new one to me. Anyone? Or maybe thinking some 75x25 suitably treated in all locations - again if easily obtainable with out paying stupid money - but feels over the top to me too 3. Fixings - 2 or 1? One makes far more sense to me, but again lot's of opinions and 'advice' out there! 4. If we run with feather edge will we have a problem with movement/gaps making having insect grilles almost pointless! The chestnut shouldn't in theory move like the softwood feather edge I've used in past on sheds etc (where it doesn't matter). Any experiences? Need to make a rapid decision - as whatever I do on the walls dictates what happens at the eaves/verge and the interface between corner of timber cladding at the interface with the eaves/verge joint. Really need to keep to 25mm thick battens as planned unless no choice to go to 38mm. No soffits / minimum overhangs. Need to order metal roof sheets / components urgent which will be made to measure for required dimensions! Hopefully somebody out there has been through same process and has all the answers please!!

ps switched to viking in end due to lead times. we were held up placing orders due to other people/companies delaying us!

no! sorry no idea...........

I feel your pain! Was a difficult process selecting. Narrowed down by decison to go supply and install only. We have Timber Innovations commencing on site next week with a Larsen truss system. I will report back when they are done. Ruled out sips quite early - yes proven systems but just didn't feel right! Careful with rafts all inclusive - I looked at this carefully early days as did seem attractive. If soil survey recommends suspended floor (as with ours) structural warranty provider / BCO may not be happy with raft. (we are on heavy clay and have deep strip footings with beam and block in end after preinsulated slab manufacturer moved the goalposts!) Careful with over enthusiastic proposals. You will also probably find initial dig and sub base will be excluded so any failure / movement this is where the finger will be pointed. And if 2 purchase orders/contracts expected the reduced risk starts to disappear. And you may find an unreasonable written contract by supplier/manufacturer is demanded (read the small print!) - as opposed to a contract in the form of a purchase order from the person spending the money! You may be offered windows too but will want separate contract probably so again not as shiny as it sounds. Might be fine of course and reputation good - but i wasn't prepared to accept risk and sign contract careful too with raft insulation providers - brilliant systems, but i know somebody who had problems with gaps etc which defeats the object! if we had the right soil would have gone with raft without a doubt. would have saved a whole world of grief with groundworker. (I know best - been doing this for hundreds of years guv etc!)

ouch - i've got just under 24m - thought that was enough!

ps - i that the Lindap half round gutter (JamesP) ? Looks good and on my list as a possible. All good or any issues? many thanks

thank you both for your thoughts - very helpful. 99% certain concluded as per sketch. Fascias first and clad over in trim to match roof. Cladding to underside of fascia (of any type!). No additional roof overhang with fascia planted on cladding which means not pushing beyond limits of OSB / standng seam. I can't be only one to have had this headache - move one thing to correct and something else is then wrong! It was more than just about wonky fascias on feather edge! please let this be my last conundrum!

Evening all, We need to fix barge boards and fascias direct to horizontal timber cladding. If cladding is feather edge (visually our current preference) there isn't a flat surface to connect to - is that a problem or am I overthinking this? (if we use a lapped cladding it will be flat). any thoughts appreciated please many thanks

having worked for and managed builders merchants for 18 years until 2003 (with a small stint at a tool/fixings distributor) I know the business extremely well. (now work for a specialist sub-contractor mainly in fit-out market). And yes it's one of the only industries left where having to haggle is the norm. You need to know the score! I did at one point consider setting up a new company - but didn't want the grief of being an employer so remained employed! The majority of conversations I have with merchants now (as a customer) tend to be me telling them what they are doing! Often poor knowledge (assume lack of training - used to be a big thing!), little commercial awareness, and astonishing how many clearly don't give a sh##! Welcome to the 2020's!! Unfortunately the 'professional independent merchants' are no longer imho. So often corporate groups just looking at bottom line doesn't help. The knowledge required to understand all products, how they are used/markets takes a long time to accumulate and very few people are interested - and merchants don't pay the rates required to attract and retain the right people. The building industry has changed significantly too - and with MMC increasing merchants will I believe need to adapt to retain levels of busiess (must already be shrinking?) - albeit there will always be a large traditional market for them. Our self build walls and roof is timber frame panels ready made out of a factory craned into position which has cut out a significant amount of procurement from merchants. They will also be more careful these days about the liabilty of providing informaton that could be deemed 'professional advice'. Most general builders merchants will I think seriously dumb down their range of products (probably already happening) and concentrate on heavyside/associated products, and timber. Lightside covered by plumbers/decorators merchants and with the likes of toolfix and screwstation who would pay double for a box of fixings / power tools etc. Builders merchants will probably continue to do well with direct to site sales from manufacturers who insist on supplying through merchants (not a bad thing) - will I assume still receive a typical 5% or so handling fee - I have had to do this on a few items, but have sorted the details out first with manufacturer. Too many have also tried to become DIY stores over time too and failed - apart from anything else it alienates ther core customers! Items we have needed have so far come from numerous businesses, including direct from manufacturers/distributors - would have had to been via merchant in past. Also used merchants of course - but from various depending what we need and up until couple weeks ago hadn't even bothered setting up an account anywhere (finally established a good contact - its the right person you need, the company less of a factor!). I can see merchants trying to sell everything shrinking - less money tied up in stock too! Already happening by default I feel with multiple companies selling specific product ranges on-line nationally with websites of varied user friendlyness - and a select few with remarkably good back up service with phone conversations possible with real people which is unusual these days with anything. And when I say real people i'm referring to those who do give a sh## and have a brain that contains common sense in addition to knowledge of what they are selling. The need to now use multiple suppliers is almost in a way turning back the clock! I could go on all day on this topic, but won't - I've rambled on enough as it is!! bottom line is (imo) as a self builder you need to know what you need and understand the market - info and opinions from merchants etc always useful but don't trust/rely on. So to get back on topic of setting up a dream builders merchant - sounds great, but good luck, plan extremely well, and be very careful........ and going off topic I've heard some ridiculous things over the last 6 months from merchants, disributors, and even manufacturers - and more so from trades who think they know better - 'I've been doing this for 30 years guv' scenario - then making mistakes and costing themselves money and time because they didn't listen and reluctance to change to new ways of doing things! One has cost me a little money. time and grief too (sloppy not immediately obvious things i found after they had completed - sorted myself as no point getting them back as they'd probably f### up something else and moan!) - needless to say that one won't be getting the next phase of works they were particularly keen to do! right thats enough, feel better now!

and how membrane is cut /folded etc? need extra? drip detail at head behind membrane? + intumescent between battens.

moving on from the supply chain does anyone have a detail please for the reveals externally? We have flat boards with windows set back midspan of insulation and doors futher back on the structural stud with compacfoam at base. Battens and timber cladding to outside. Windows and doors fixed back to internal 140mm structural studs and sealed direct to boards - or am i missing something here? should they be lined first with membrane??? I don't think so but seems to a detail thats top secret! Timber frame company leaving openings covered by membrane to avoid ingress of rain whilst waiting for windows, so this won't be opened up until window fitters ready. Windows and doors will be fully sealed with air tight and precompressed tape etc. But doing some serious head scratching here how the connection is made at the outside to avoid moisture ingress into boards. Or am I overthinking it? Timber frame company / window installer all saying 'by others' - need to get this right! Also now thinking is there any risk of condensation under extended sills? extract of drawing and image example of intent herewith.............. any thoughts appreciated please.............kr ....mextract ref pro passiv to reveals.pdf

we're not as yet in contract but we will almost certainly be using Nordica - who use Viking and Slowinscy. We have decided on the latter. Transparency with regard to the manufacturter / actual product* They will be providing a deeper base to window to ensure adequate fall on extended sill. Extract from their proposals: 1* Frame packer 30x105mm (A30*105_40_M) Length 700 mm, color: Lacquer Regarding fall on sill there's nothing in building regs! Which are supposedly there to protect us - there is lots of good stuff in there, don't get me wrong, but there is lots of daft stuff (some ridiculous) in there too as we all know. But there are simple things missing too which is just as daft! Whilst talking to numerous people/companies i discovered not unusual for extended sills to end up flat / almost flat. Which in theory complies with regs - because there isn't one! Wouldn't suprise me if some end up running backwards perhaps!! * many UK suppliers rebrand and have found resistance by some in providing info and insist they are the manufacturer when they clearly aren't, but why I have no idea as this is not a problem! (I come accross this regularly in my day job, on the other side of the fence, with competitors doing the same and buying whatever they feel like to suit their margins!). With regard to who 21deg use I have no idea as didn't get very far - they didn't want to talk and didn't even bother to respond, and IMHO no point chasing people like that as my assumption is it's not going to get any better! Assume supply only too? Their other departments were somewhat mixed, some ok, but needless to say we won't be buying anything from them! Originally thought it could be a one stop shop and they'd be super keen with potentially one point of contact to reduce my stress levels! But alas not... ASHP/MVHR/PV we're procuring through heating engineer. Compac foam easier through UK distributor!

We had shortlisted Nordan (no.1 at one point) but crossed off mainly due to not offering extended sills and not understanding (until I pointed it out) the adjustment required to maintain a fall. And wouldn't offer install, even though they were happy to recommend installer - who would have supplied the extended sills. windows would have needed to be ordered undersized - they proposed packing up with ply/similar which i wasn't happy with for obvious reasons. Shame really as otherwise ticked all the boxes and communicated well - more than I can say for numerous others! Decision almost made now and will be placing an order very soon based on supply and install with another company. Been dragging on as BCO was indicating escape windows required which would have meant increased opening dims - but once discussed further regs approval finally arrived as current design.

spoken to a couple of companies again - as assumed they clearly hadn't listened previously! People have been the biggest headache from day one on so many things - something i didnt anticipate going into this!!! One is now proposing fibre reinforced flowing concrete 75mm thick which is almost as original intent! (and I can't go any thicker). Waiting for call back from the other thanks all for comments - glad it wasnt me going mad!!

no confusion! pls see earlier responses / comments!

thanks John.........

maybe none of them listened then! frustrating as original intent was no screed with insulated precast 'slabs' ready for self leveller, but had to change as manufacturer moved the goalposts. But too late then to change the timber frame!

thank you - 75mm with fibre? just sand i assume to get around pipes?

Morning all, opinions and experience please on type / thickness of screed.....? beam and block; DPM wrapped up and over perimeter supporting walls sealed to DPC; 150-175mm PIR in 2 layers staggered joints and taped + upstands; membrane; UFH pipes; floating screed current intent is 150mm PIR + 75mm reinforced floating screed (type / spec tbc) Screed will be laid before walls and roof are on - timber frame company also building internal non load bearing stud walls straight onto screed. Reduces risk and grief! Continuous build with no option to down tools for a week or two whilst a screed goes in after roof on. Confusion and lack of trust now klcking in - screed companies quite excitable about liquid screeds and keeping to a minimum thickness and increasing insulation - which is fine. However, I'm now losing confidence as it seems the ones I had narrowed down to simply didn't listen with regard to the fact this would be open to the elements. Appreciate can't do any of the options in rain, but moving air (wind) and sunlight is unavaoidable! One has now suggested I put up a temporary roof which is bonkers! Sounding like I may need to revert to original intent? Which would be a shame as liquid screeds sound very good and also less cost! guessing I'm not the first person with this conundrum!