jack

The main potential issue for me is that if there are enough objections, it gets called into committee. While you should, in theory, not be any worse off, I suspect it'll be easier, cheaper and less stressful if you don't get the planning committee involved. If they get it wrong, you have to appeal, which is more money and time, even if you're in the right. So basically I'm all for reducing objections as a general principle. I posted something on this general point in the last few weeks. I'll see if I can dig it out over the weekend, but the essence of it was to be careful about being too open with your neighbours about your plans. The last thing you want to do is try and keep everyone happy by listening to their feedback on your detailed plans, then realise it's literally impossible to keep everyone happy because they all want different things. Then you've by definition seriously annoyed one or more of them by not implementing the feedback you asked them for, so they object. I think it's better to gradually get them used to the idea of development in a social context, then slowly allow the general to become more specific over time. By the time you submit your planning application, everyone around you more or less knows what's coming and there are no surprises. We got a bit lucky, but this was the approach we took and we had no objections to our plans to knock down a small bungalow and build a large, very modern two storey house with three times the floor area!

Underfloor cooling is usually cautioned against due to fears of condensation. If you don't cool it down so much that there's a condensation risk, you'll be fine.

I personally think it's hugely important. We in theory have slightly better than building regs levels of insulation (although I do have my doubts about how some of it was installed when I wasn't present) and I'm not at all happy with the levels of sounds insulation that's resulted. If doing this again, I'd up the amount of insulation, use resilient bars everywhere, and ensure that all the installation and detailing was perfect.

Yep. It's about decoupling: less surface area = less energy transfer. Probably some minor amount of energy absorbed in the bar itself (which will be even less in the "top hat" style), but decoupling is the major factor at work here.

Here're a few: http://bit.ly/2cPUaNw The reason you need all the other stuff is that different elements are better at different types of noise and different frequency ranges. I wish we'd spent more time on this - I'm surprised, for example, how much noise from our TV room leaks into the bedroom above it (which thankfully is only a spare room).

I think you've gotten very lucky with these guys. Definitely a better finish than we got, especially in the corners and around the edges.

Welcome. Lovely part of the world, Vancouver.

It's not voodoo. It's an extremely common part of sound proofing but generally it's used in conjunction with other measures like insulation, green goo and multiple layers of board.

That's a really nice finish!

Why not call the planners and ask for the source of the information without saying who you are?

All I will say is make sure that the you test fit the cills before finalising window positions. You can see on the drawing you've done that you had to change the angle of the cill from the Nordan detail (which I know you've just adapted) and chamfer the frame. Are you sure that you can get the required fall on the cills with your current window position? We had an absolute world of pain over this point.

Agreed on the Fermacell, although if you can't use the fine surface treatment (maybe because of access) you may find it a bit rough-textured compared to plasterboard. Be careful how close to the edge you use screws - even with the special screws they recommend, we had some splitting.

Never a truer word said. Wish we'd had some advice about this before our window installation. Caused a lot of consternation with the people doing the plasterboarding, and we ended up with bits of airtightness tape peeping around the edges of the plasterboard in a couple of places.

Ah, lucky you! Mine's more or less exactly as shown above, but without the DPM!

It might be belt and braces, but I was told it was needed to protect the frame from condensation dripping off the underside of the cill. Unfortunately, ours doesn't have any either (installer error), and when I went to install some afterwards found that they'd permanently glued the cills in place!

Light on details, but sounds something like a simpler version of zeolite storage: http://www.independent.co.uk/news/science/heating-vermiculite-potting-plants-heat-storage-summer-sun-winter-swansea-a7234406.html

In defence of the builder, none were perfect, but this one was much worse than all the others. My mate is really, really happy with the work that's being done. I just bite my lip when he shows me around, same as I've taken to doing with just about every other recent extension I've been shown around by various friends over the last couple of years. This is also a rare case of me raising insulation for discussion. I've learned that people don't know and quite literally don't care, and indeed, get defensive if you try and discuss improving insulation and airtightness. The attitude seems to be that it's fine if you want to build an "eco-house" like we did, but that all that stuff isn't relevant for an ordinary build. All anyone seems to care about is how big the kitchen is and how wide a set of bifolds they can get away with.

Even then, perfection isn't assured. From a friend's extension going up at the moment: He mentioned that their current house (loft bedroom) is quite hot at the moment so they're getting air conditioning upstairs. I asked about increasing the insulation depth instead or as well, but he said they don't have the ridge height.

Could your system have more air in it than next door's? I was surprised how much entrained air we had in ours when we first set it up - took quite a bit of effort to get it properly "burped". We also had lots of pressure changes until we got that right.

Argh, what a ball ache. Good luck finding the leak. Is it all one circuit? With luck you'll find the leak without having to take it all up. My electrician (otherwise the most careful and conservative guy we had onsite) put a screw through our UFH pipe - in our MBC slab! It was right before we had the screed concrete laid (for polishing). The screed guys pointed out that the bit of protection the electrician had knocked up over a cable duct into a recessed floor box in our study wouldn't allow enough concrete coverage to avoid cracking. He therefore had to come up with a new bit of protection in about 10 mins. Months later, and more than a couple of weeks after we pressurised the UFH circuit, my wife started swearing downstairs one morning because she thought the dog had taken a wee in the study. Looking more closely, we realised that there was far too much water, and it was clear (thankfully this was before we added glycol). Cue a day with me and the very apologetic electrician carefully chipping into the main slab under the screed, until eventually we found a tiny pinprick caused by a screw he'd used to hold in the bit of steel over the cable duct. He hadn't realised that the UFH ducts came so close to the box. We had a near miss on the same day when I came into our front hall to find one of the screeders about to start drilling his third hole into the slab for a rawl plug to screw down the stainless steel edging for our mat well! Thankfully he seems to have missed the UFH pipes! Good luck.

Four weeks seems a long time to wait to do the grinding and polishing on hard concrete. Our guys suggested ten days to ensure it wasn't completely hard, and in the end did it starting on the 8th day if I remember correctly. I'd need to check my notes, but I believe it only took the two of them two days to grind down to "pepper pot" (some aggregate showing randomly in patches, rather than across the entire floor). You're taking quite a bit more than that off, so I guess that's part of what's taking the time. Yours looks a similar shade to ours - very nice!

I suspect we're coming into the most dangerous time for potential overheating. The sun is lower in the sky so penetrates further into the house and under overhangs, plus we still have some warm periods. Certainly our house has at times been a little stuffier lately than I've wanted but it's generally been fixed by opening windows. We haven't yet bothered to enable cooling on the ASHP and I'm not sure we ever will. In part this is because downstairs is always comfortable - it's the bedrooms that get warm, and they'd get hardly any cooling effect from reducing the slab temp.

If the question is just whether to put pipes into the (presumably insulated) slab, then I think you'd be crazy not to, mainly because you simply can't realistically go back and do it later if it turns out you need it. If you don't need it, well at least you can tell a prospective buyer that they're there if you ever sell, because no-one will believe you when you tell them there's no UFH or radiators! We're more or less Passivhaus standard, and I think our house would have been downright cold in the middle of winter without the slab being heated to around 21-22 degrees. We have the additional problem of concrete floors throughout our ground floor - this makes the floor, and hence the house, feel cooler than if it was wood or carpet.

Last off-topic, I promise (well, for this thread!) While my musical tastes mostly lean to the heavier side of alternative and electronic music, I make an exception for Total Eclipse of the Heart. In my opinion, it's one of the finest pop songs in history. Always gets put on at our house later in the evening when people's voiceboxes have been suitably lubricated. Never fails to get a rowdy singalong going!!!

Are you going to the Hunter Valley? Make sure you try an aged semillion! I grew up in Sydney, near the foot of the Blue Mountains. I haven't been back for nearly 8 years, and moving into the new house (and the removal of a lot of the associated stress) has left me with time to get homesick recently. We're going back next year with the kids. If you want to visit a beach, head for Bronte instead of Bondi (better yet, walk along the cliffs from Bondi to Bronte and have breakfast at one of Bronte's cafes - the Bogey Hole is, or at least was, awesome). For amazing food (particularly Thai, which Sydney is famous for) and coffee, head up to Crown Street in Surrey Hills, south of Foveaux St. You can walk it in around 30 or 40 mins from Potts Point. Have an awesome time. I've just been looking at Sydney on Google maps - argh, homesick!