Tony L

I don't want my garage to be completely airtight, but I was thinking, if it was a lot more airtight than most garages then I could run a PIV in there to pressurise the room & dry out the cars when they need it - some of my cars are old & may be left for weeks at a time without being used. Also, I might heat the garage if I'm working on one of the cars during the winter. I have the PIV that was rescued from my bungalow before it was demolished. I'm thinking the best solution may be to have a regular garage door, for security, then some king of curtain arrangement inside to increase the air tightness.

No, but I'm planning this (that's if I have any money left when the build nears completion). I discussed my plan with my SE, & my drawings show standard 7N blocks laid flat - so my wall that the stairs will hang off is 215 thick (+ finish) rather than 100.

These were my first thoughts. If you've identified an affordable, reasonably airtight garage door, I'd be interested to hear about it, please.

Just confirming AeroBarrier is indeed zero rated for new builds. & their responses to two emails I sent were very helpful, although they weren't prepared to say, "If we come along & your building is already at x ACH, we'll guarantee to get it down to 0.6 or better.". That's not a big surprise really, although a guaranteed result would certainly mean I'd be more likely to go ahead with them.

There are different ways of dealing with this problem & each way carries different risks. If it were me, I’d be saying he’s broken the contract because he didn’t, “provide a high quality outcome for the works”, (that’s a quote from your contract), so there’s no reason the client should be bound by a contract that the builder broke; he’s off the job, & he’s not getting any more money. If you want to carry on fulfilling your side of the contract, so the builder has no opportunity to say you’re in the wrong then you need to write to him, if you haven’t done so already, to tell him the work is no good. Just two or three sentences should be enough. Do not mention anything he’s done wrong other than the Posis & the steels – you don’t want to give him the opportunity to argue, at length, over some trivial matter. It’s highly unlikely he will order, pay for, & wait for delivery of a full set of Posis & steels, & have them all installed & looking as they should do, within 14 days of receipt of your email/letter. & if he tells you he's going to fix his work, as @saveasteading says, you should insist on a formal proposal for a schedule of the remedial works, so he'll have that to squeeze into his 14 days timeframe as well. Also, your contract says mediation should take place. Your contract isn’t specific about the kind of mediation, so this would just need to be a short meeting with you, the builder & a mediator – it doesn’t even matter if the builder chooses the mediator – you don’t have to agree to the mediator’s suggestions. So if you want to still be seen to be upholding your contractual obligations (even though he broke the contract), email him to offer mediation, at your site, one day this week. As I say, if it were me, I'd not be even giving him these opportunities.

Good luck, @Nick Laslett, & thanks for your airtightness details. You certainly sound as though you know what you're doing, so I have saved a copy of your post in my "Airtighness" folder, which I will hopefully remember to look at when I start to select (or others start to propose) which products will be used in my build.

I should think you're right. Email sent. I'll report back.

I'd worry about my lungs. Do the AeroBarrier team zero rate their invoice, @Nickfromwales?

Don't say this until you know the cost of correcting the work is a lot less than the amount he's going to say you owe him. If he's going to get nasty with you, your starting point for negotiation should be: He's broken the contract, by consistently undertaking poor quality work & overcharging, so you're going to force him to pay a competent builder to undertake the required remedial works, because he has demonstrated over the course of several weeks, he's incapable of doing the work to an adequate standard himself.

Well done. You're managing this situation well. Keep us updated. I'm following with interest, as I had similar problems with my first builder (& I'm still only just out of the ground with my build). I also had to defend myself against threats from his solicitor, so don't be surprised or concerned if that's your builder's next move. He will concede once he realises that you're more capable & robust than his usual clients.

Congratulations. That looks like a splendid location. I'm looking forward to hearing more, as work progresses.

Good point. The office/gym wouldn't even need to be behind the house to fall within PD - just no closer to the road than the front of the house. However, I'm sure OP will have a good reason for wanting it by the road & if it's going to be there for the next 20+ years then it's worth a few months arguing with the planning department, if that's what it takes.

@ProDave The site entrance is on the plan, but the drive isn't shown @neqinox I think I'd build the garage first - it's PD (unless PD has already been removed for this property, perhaps as a condition of a previous successful application). Then put in a planning application for a bigger than you want gym (some LA's love to say, "no"). Then you can negotiate down to the size you want, & the LA will feel like they have a win, because they think they stopped you doing what you wanted to do - that's the way it seems to work where I am, anyway. You've already got your garage, so if they remove PD when they grant permission for the gym, it doesn't matter.

Congratulations on your purchase, & welcome to Build Hub. What's the first big thing on your to do list?

That looks good to me @Tom, but then again, I know nothing about building. Please update this thread as your work progresses. I am considering having a go at mine when the time comes, although, in my case, I think I might build temporary stairs (so they won't need to look perfect) then if there's any money left when the house is just about done, I may be able to have floating stairs, hanging off my block wall, which is spec'd to look like the wall in your picture.

Are you saying you were refused a PD cert? How big was your proposed outbuilding? The one described in the link is 375m2, which is very different from 40m2. I don't know what @d438a1's workshop is for, but if it's to work on cars, for example, you could fit two cars in there, but then there wouldn't be enough room to work on them.

Following this with interest as my design has washing m/c & dryer against the wall that will separate the utility room from our snug/TV room. My number one strategy is to buy a Miele washing m/c. My mum has one, & it's so much quieter than my Bosch. The Miele dryers & dish washers are quiet too. I may make the stud wall a little thicker, with offset suds (ie each upright is only connecting to the board on one side of the wall or the other) then the sound absorbing insulation snakes between the uprights.

@boxrick, I think your blue ASHP is too close to the window; it should be 1m min. away.

Yes, sorry, I forgot to mention him. So he's £2300 + VAT, but we have quite a few steels going in. I shouldn't think you'd have to pay quite so much, @Crofter if you design a house that's a similar shape to your last one.

I suppose when I get my test done it will be easy enough for the tester to give me an ACH figure & a permeability figure (if I've worked out the m2 figure). I now realise that because my house has poor form factor (thanks to the horrible people at my planning dept.) it's going to be quite a lot more difficult for me to get close to the PH 0.6 ACH target than it will be for most people that are building an actual PH house, with good form factor.

I'm leaving the answers for 1) & 2) for the BH experts. I'm definitely not one of those, but I have recent experience of 3)... I did my own drawings to get PP (& if I can do it, it will be no trouble for you to do it). It's a 1.5 storey 4 bed house. 3 dormers; each dormer is different. I employed an arch tec to turn my drawings into construction drawings & deal with BC. The AT's fee was £4,200 + another £200 perhaps, for some add-ons, & no VAT. He turned out to be no good (I think he may have age related cognition problems). The new AT will cost £6,000 + VAT, but there are no add-ons & he'll keep going with amendments until BC are happy & I'm happy, & this is covered by the £6k. I'll have to pay extra for the BC submission fee, SAP, proper heat calcs if I want them, QS/bill of quantities - perhaps you can do this yourself, given your experience. Hope this helps. I'm normally the one asking loads of questions, so it's good to be able to try to help someone.

There's more on ACH measurement vs permeability measurement here, with some diagrams, if anyone's interested: https://efficiencymatrix.com/commercial-enclosure-air-tightness-testing-targets/

I am very grateful for all the advice I'm receiving regarding building my house & the first few pieces of advice on how I might best deal with my partner, whose views don't always align with my views & don't align with the general views of the BH community, but you haven't convinced me that your way of dealing with somebody you've never met will work better than my way. This is because I've had thousands of conversations/negotiations/arguments with her over the past two decades - so I think I'm in the best position to judge which approach might work best. None. There's no architect. I drew the house & did the PP negotiation. I've just appointed a new arch tec to draw it all up properly & specify all the construction details, which I'll be able to check, thanks to everything I've learnt here on BH. I'm not going to share my postcode, only because I'm trying to maintain some level of anonymity, so I can speak freely about the planning dept & BC dept at my local authority without getting myself into trouble. For the same reason, I refer to my partner as my partner/her/etc because she has an unusual name. It would be nice to use her name, but then it would be easier to identify our location. It would be great to meet some other BHers at some point, but I'm too busy over the next couple of months. Thanks, Terry, & thanks @ToughButterCup for your response too.

I don't think it has to be the front door. I think it can be the "back door" (on the side of the house in my design) so long as your WC can be easily accessed, in a wheel chair, from the back door.

Thanks, everybody, especially @SteamyTea for putting the spreadsheet together. I've not started playing with this yet, but I have learned about Bin Method.