Besidethewye

Just plumbing in the heating system. It's more complicated than I had hoped. Two separate UFH systems and three radiators via another UFH manifold with three pumps so each can operate independently. Thermostats brought back to two separate wiring centres. Was recommended to use non return valves in the returns from each manifold to prevent unwanted circulation in any circuit that's not required. This instead of two port valves to bring each circuit on. Happy to do away with the two port valves if they are not needed in the interests of simplicity. Two manifolds will use actuators with the inherent delay in opening valves - the plumber is suggesting that we fit a bypass valve so that as the actuators slowly open the pump is not pushing against closed valves but recirculating through the bypass over pressure valve. The third manifold is always open - no actuators - so pump can switch on immediately and will flow with no problems. Planning to take the always open circuit thermostat back to one wiring centre and use the boiler enable and discussed using the actuator switch to run the pump - talking to the supplier this would work direct but might put in a relay. Just wondering whether it's worth having a time delay relay to hold starting the pumps to manifolds with actuators rather than letting the bypass valve take the strain.

@JSHarris I discovered when the windows arrived that they all sat on 30mm deep 'travel bars' which meant that the windows were 30mm shorter than I had expected - I have no recollection of seeing that anywhere in drawings or correspondence. The change in the relation between height and width would not be obvious to all but the keenest eye.... One thing that the window fitters did say was that when people are looking for level thresholds and putting notches into slabs they should make the notch significantly deeper (further into the room) than needed for the window/door so that they can get at the frame from both sides and not just from the outside.

@lizzie that would be really useful - just in case....do have to work out my level threshold details and the right way to do the drainage and support the slate/stone etc. we had endless trouble with the level threshold thing - for reasons I do not understand none of the notches put in our slab were right (and the slab has an interesting set of slopes in it) so we had to build up as needed under each of them which took a lot of time. @Roundtuit I would love to get the manufacturer to take a look at the installation before it's too late. Will push them to come and see it.

Thanks all The frame is engineered softwood with ally clad outside. I would say confidently that this is an installation issue - the windows themselves are top notch (and should be). Install was by the supplier. So I would say that the high spot in the base and the twist were added on install. I think the latest attempt to make it work which involved removing the fixings and a set of wedges to try to get the twist out and the base level may well have bent the ends down and put the high spot in the middle of the base. What I want to avoid is a window that sort of scrapes in now but can only get worse over time - and I assume it will sag more over time and need to be adjusted up.

A quick question (or not!) We have a large triple glazed window (1200 wide, floor to ceiling) - a big ask on the hinges I know but there was no hesitation in supplying it. Tilt and turn. We have had endless problems and over a year now it's never been adjusted successfully. The frame went in with a twist and also has a slope and high spot in the base. The twist is less but not gone now and the window operates as well as it ever has. The adjusters are at the end of their adjustment - window fully up at the hinge side and you can feel it scraping the spacer at the non hinge end. From what fitters have said and my thinking is that over time it's only going to sink and need to be adjusted up to clear the non-hinge end. The latest assurance was that it does not matter that it's at the end of the adjustment as there's no reason it would move. My instinct is that there ought to be plenty of adjustment available to have any hope of the window operating successfully for the 25 years it should be working for..... Any thoughts welcomed and appreciated.

Many thanks for all the suggestions - not short of a few options there then!

As I work my way through the next stages of my project I am going around in circles about sound proofing. The old place we had was a steel frame with floors fixed directly onto joists with no attempt at sound proofing anywhere at all and we never noticed it being a problem. Now we've put up an MBC timber frame - with posi joists and 22mm chipboard nailed and glued above. I plan to put in engineered wood floors upstairs and was assuming I'd put in acoustic underlay of some sort, rockwool in the floor space and doubled up plasterboard under. The walls are filled with cellulose - the building's three floors and the stairwell will carry sound pretty well all the way up. Looking at the underlay options there seem to be many that are thin with not much benefit in terms of noise and then eye wateringly expensive thicker options that offer significant sound reduction. Any experience from the MBC builds that might help square this particular circle would be much appreciated Oh and as a supplementary the stud walls come with a sheet of 9mm OSB on one side - any idea of how much this contributes to sound reduction? I was told the other day that there's some advantage in having different weights of covering on each side of the walls to reduce resonance - I couldn't find anything with a bit of googling that gave much on OSB in the wall for sound.

Nick and JS thanks again - will indeed aim to have as few pipes against the external walls as we can (things are a bit complicated by the shape of the build and the ring of steels/glulam beams that separate the inner part of the build from the rest at first floor floor level). But will make sure we have a plan before we go too far with fixing things in place!

JS thank you for that - that sounds like belt and braces (and there's a lot to be said for that!). On that basis you're spreading pipes (and cables) around rather than running them up together. Without having started I am assuming we will have plenty of places where things have to cross and with 35mm to play with it may all get a bit tight. I am anticipating a certain amount of resistance to being really fussy about the airtight layer but good to have some back up!

Hi there - newbie here and apologies if I am repeating and reviving a discussion that's been done to death. Just about to start the first fix plumbing in an MBC passive house with the smart ply air tight board on the twin stud walls. I am impressing on everyone the need to not compromise the airtight layer and wondering what the best approach is going to be with clipping pipes (and cables) on the walls in the service void to avoid holes in the air tight board. If indeed we need to worry - presumably if we have neatly seated screws in each hole the sealing is pretty effective and screws ups should be redone with holes taped? Any suggestions gratefully received.