BenP

Hard to tell. We regularly submit pre-applications here (architects) - some are useless and others are gold. It can really depend on whose desk it lands on too. For my own house we received an eight page response and some nice design suggestions which is responded positively too. It helped wrap up the narrative and we obtained permission after 5 weeks. On the flip side we are working on projects at the moment where we have heard nothing for 3 months and the LA are no longer accepting new pre-applications.

Do it! It can't be done once you're in. The way we look at it on ours is that figures like that challenge our budget, but we aim to be there a long time and would rather leave rooms like en-suites unfinished. We've insulated over our timber frame with a complete layer of wood fibre and it is fantastically reassuring knowing there's very little in the way of cold bridging ?

So you're nearly there. Youre ready for DPC, coursing block and then final infill floor block. Another block to bring it level on the outside and then a concrete topper. I would always add the floor/channel drain but you may be OK with some good falls.

See attached - taken from a very basic set of Building Regs drawings we produce. I've just added a red line to indicate a DPC under the Beam and Block. These drawings are usually seen at 1:50, not 1:5!!!! BP

Min 65mm, usually designed at 75mm. This is helpful: https://www.labcwarranty.co.uk/blog/floor-screeds-and-underfloor-heating-a-best-practice-guide/ Not sure about the option for fibres - I've heard mixed opinions!

I don't think there is a right or wrong answer TBH - in our case the internal walls were put up as they were part of the 'stick built' timber frame solution. It has indeed made screeding more dificult and some of the airtighting details are more complex than if we had put the walls up after screed and VCL! But having all walls up and done was more valuable to us.

Hey - sorry for the delayed reply - it's been a busy yet productive Christmas. Remaining windows are finally going in today too! Not quite sure understand the question.... The double batten you can see it just two close to each other to ensure 600 fixing centres for the cladding and as per the timber frame within. No DPC either although I have decided I'm going to redo some of the battens to leave a small gap so I can introduce a small 'tray' to get any water coming down the membrane away from the window head.

Fabric first baby! Our extension is all about pretty decent levels of insulation but still balancing cost and impact on space (we had limited footprint to play with due to specific planning policies). Super airtight, decent MVHR. UFH designed to run at 35 degrees with close pipe spacing. Solar PV going in now as it saved us nearly 1000 tiles (so nearly £1000). Essentially making the PV system cost just over £2k as a DIY install. Existing cottage will be next - upgrading a 9" solid wall structure. Existing combi boiler will be kept until it pops! Probably going to go for a clever unvented cylinder that takes excess solar energy, soonish. Following that, we'll then look at clever tech...

I wish! I'm going through it at a rate of knots. I think it may be holding the house together!!!! Ecomerchant have been quite speedy for me? Check with PH Store, Mike Wye and see if they can do something next day?

Hi, We've just today put the final fixing in for our wood fibre sheathing board on roof and wall. 60mm on the walls too. As you suggested, we've used the Ejotherm fixings to hold the sheathing board back to the timber frame. Typically a couple per board. We're now in the process of fixing back the vertical battens with Heco fixings (https://www.heco-schrauben.com/screws-accessories/screws/heco-topix/). 180mm perpendicular (straight in) and 200mm at 60 degrees (for suction and sheer). We ordered the insulation through Ecological Building Systems who organised a fixing plan from Heco. I think you can go direct though. The plan basically says where fixing centres are closer together (i.e. corners of the building). Whereas the middle of the long walls the spacings are much further apart saving on screws. Couldn't quite believe the cost of the them though..... Pic for good measure.... (every other batten done for now as I'm working through limited stock!) Cheers

Yep in theory you should be very careful with copyright etc. The link above from the Planning Portal is good - we typically use MapServe for ours. Interface is good and enables us to download digital data, cad, etc etc.

Hi, We're about to start fixing our breather membrane onto our wood fibre insulation sheathing board. Fixing advice from Pro Clima suggests stapling the top layer and then taping the overlap from the above layer. On the walls however, the staples (sized as advised) just have no hold on the insulation board. The roof sheathing board is much better. What am I doing wrong? I'm not expecting a solid result just enough to hold it in place until I tape the above layer and ultimately put my vertical fixing battens against it... Cheers.

826 usually equals 900/910 structural opening. Quite easy to remember with Metric doors as they go up in 100mm increments!

Not yet @SuperJohnG - the build has started now and I'm a little occupied. Have even started using the Vana tape - blimey it's sticky.! Anywho, roughly speaking I worked out to buy over here my order would have been around £2300 inc VAT from ecomerchant or similar. My total order cost from Germany was a sniff under £1600 all in. This was for 2x roof membranes, 2x wall membranes, 3x intello plus, various sizes pipe grommets and 30 rolls of Vana. I hope this helps!

Our internal walls are that!

@saveasteading - 140x38 stud. Lintels are 225x50 x3. OSB on the inside to give me a good working surface to VCL, service void/batten out. Gutex board is currently fixed in place with 2 or 3 thermally broken screws Ejotherm STRH, these aren't structural. On top of this will go the breather membrane tapped for windtightness. This is all held back to the timber frame with 38x50 treated battens using Heco screws (Heco provide a fixing design but they were ££££). Cladding on top. ?

Hi. I can only echo the above - it's the similar route we have taken. Rockwool Flexi between studs and 60mm Wood Fibre board over. Ready for rainscreen cladding / weatherboard. Flexi infill is very simple. Push fit, no gaps and has reasonable heat storage capability. It was under half the price of a sheep's wool or wood fibre flexi batt. A bit itchy to work with but I was actually watching two others do it whilst I started the Wood Fibre. One thing many forget with infill insulation only is that you end up with so few gaps to actually fill up. See the pic attached and note the amount of triple studs and solid lintels.... BP

Thanks @Conor You've said enough to make me save the cash for something else. It looks like BPC do a good amount of work to help design it well too.

Afternoon all, So through work I've had dealings with GBS - they've provided me with a quote to design and supply our MVHR. Circa £5k. From reading on here I've since had a quote from BPC for half of that. I assume the design input I'll get from GBS is going to be more bespoke and hopefully better. They also only use rigid ducting and stress that the system will work as well as possible and be inaudible. BUT. Is it worth the extra investment? I'm conscious that once I've put something in I can't change it. From a self build and install point of view I'm also attracted to flexible ducting as a few solid beams have already appeared in the posi-joists!!! ? BP

At least it will mean the boards are actually being installed! ?

It begins! Got my eye in last night trimming the grooves from the bottom of 10 or so boards that will form the starting course. Makita 190mm circular saw with a 12t wood blade is like going through butter. No clogging up either. Feeling confident about trimming for window openings etc now. Cheers.

Thank you both for the advice. Timber frame started last week so I'm hoping to get going shortly - can't wait! BP

Any advice on cutting our Gutex boards? I see alligator saws are perfect but Id like to avoid more tools in the shed! My options are a circular saw hooked up to a dust extract to keep things clear - I've read a larger tooth rip blade is perferable? I also have a reciprocating saw which I'm likely to need for any angles. I see pavatherm do a specific blade but it's not cheap! I know many of you have installed similar products.... Ta

We opted for Rockwool Flexi between our studwork. Wood fibre board over to wrap it up. The flexi came in 50% of the cost of wood fibre batts or sheeps wool.