tanneja

@Russell griffiths to be honest internorm with alu clad UPVC looks spectacular, and prices same or less than all other quotes we have had from Norsken / Rational / Schucco. I'm sure its the concession to UPVC which brings it in below everyone else, but its a change we were comfortable to make. I managed to get myself mixed up on the diagrams, indeed 3 is inside the blockwork. WHat relative thickness of EPS would be helpful on those returns? One of the EWI guys said he could do that in 10mm, then have near 20mm render. My concerns with that were whether 10mm would be worthwhile, and whether losing 30mm on the top and sides would then make the window look strange given the bottom would be larger by some degree (please note the walls will be in white render, window likely anthracite grey).

@MarkyP, have read your GBF post of your installation, and seen your windows 60% out of your blockwork. With the chance to look back at the process, and how the windows are performing, and any other methods of combining windows with EWI, what product would you use to bring windows somewhat proud of the blockwork? For reference, our internrom windows are 93mm deep, and thinking of 100mm EPS (if the soffit can handle that, will know that next week when the roof details are finalised), curious what % overhang you would do in that circumstance. Everyone thinks I am mad for thinking of anything other than these heavy expensive windows (that are quite slam-like in the way they open close) being firmly attached in the blockwork. An issue with this window approach is the window company will do fitting and plan to do with expanding tape, but would that have as much value with only a % of the window in the brick? I would then be reliant on EWI installers to ensure they have some kind of air tight fitting of the EPS to the frame. My builder is amazing, and is happy to do an EWI course to help us do this ourselves if lots cheaper or we aren't confident I would get the finish we want, but we are time constrained too, so its a delicate situation to balance.

@Mr Punter I offer my thanks for those pictures, and I felt I wanted to achieve 2 at the least. EWI installer seem to have no interest or experience in this approach, interesting standpoint when their product is to maximise thermal insulation, being unconcerned of clear thermal bridges when the client is open to widows being optimised, as they are all to be replaced anyway. What hardware or installer would you recommend?

@Russell griffiths Do you have the contacts of any suppliers/installers who might consider the south east? Logically, if the heavy windows (triple glazed Internorm) can be held robustly and it doesn't threaten the airtightness over time of repeated opening and closing, the second and third options are clearly thermally best. Neither EWI installer today would entertain anything other than the windows being entirely in the brick walls. My builder likewise thinks I am crazy, I showed him pictures of the steel brackets used on some of the projects here, again thinks I am bananas. @MikeGrahamT21 I must say I don't want to be worrying about the rigidity of any of the windows in their place, and the airtightness being compromised by any movement in the EPS. I can't seem to find any brackets online. Would you recommend them over a wood frame or a compact foam frame? Did I forget to say, budget already stretched!

Sorry, I don't follow, yes MVHR planned to combine with those other home revisions, have I misunderstood you?

@Mr Punter, when you say moving out windows towards EWI, do you mean up to be flush with the face of the solid blockwork, or even protrude a percentage of the window into the EWI layer? The quote we just had around dismissed the latter entirely saying the fixing brackets are flimsy, not something they recommend at all. How impactful would the technique be where the EWI isn't overlapping the window frame, the window is sat back to be flush with the blockwork, and render is carried back on the return faces of the EWI towards the window? In this scenario, there would be a rim around the window frame which is essentially render covered brickwork, although it would be quite thin in relative terms (but a fair bit of length if the perimeter of each window).

Thank you @Nickfromwales, I won't know for sure what air tightness we have until the build is done, but given we are pouring new solid floors, adding EWI, new triple glazed windows (no trickle vents) and new rood and ceilings throughout, it is almost a new house. I have my fingers crossed that trying to bring these features together results in a house that 'works' as it should.

First EWI firm have suggested that the windows are left fixed flus on the front of the blockwork, and that the EWI (Graphite EPS) would be extended over the frame of the window 30mm around all edges. Part of me thinks could be ok as plan to be Tilt and turn windows, although its losing sight of some of the beautiful frame I plan to pay for with Internorm, and would that get complex with the cill at the bottom? Is their strategy the most viable / secure relative to bringing the windows (to some degree) into the EWI layer?

I will be calling BCP later today to see what my options are, if people are considering decentralised units it feels like the only downside of a deparate single room MVHR for part of our property will be the extra cost and burden of two sets of filters. Just so I am clear, are the combinations of ducting available are 75mm circular, then 51mm x 114 oval, then have I seen on a post mention of 215 x ?? Many thanks James

Thanks @MarkyP and @ADLIan, both very helpful to me and my builder. To gauge where we stand with our building we have a couple of EWI installers coming around to quote tomorrow. It would seem 100mm of graphite EWI would bring us to the redecoration regs, but the soffit overhang would be a token. Builder will know more about whether he can have more roof overhand when he takes off the existing in a week from now. Also plan to visit an internorm seller in the next few days to discuss installation with EWI involved, surely it is something they are used to!?

Looks like it belongs in the back of a DeLorean! We had a guy from a tech forum spec our house with cabling diagrams to cover various circuits from CCTV to home network, but how they will all link together is beyond me. Running the cable for now and anything about the integration of the systems that my sparky doesn't have experience with (probably most of it) I will likely need to hire a smart home professional to figure out. Only one I asked so far is asking for £500/day in just his labour, and he was familiar with all the tech.

@Triggaaar what decisions did you make in the end please? Thanks

@MikeGrahamT21 you are so right, 2.2 currently, my mistake. I am struggling to guage the difference in comfort that 0.38 (EPS) and something around 0.2-0.3 (Kingspan K5) would mean in real world terms, and whether the extra cost would be justified if we plan to stay here for 20 years. @Russell griffiths that is reassuring to say not get hung up with U values. It is such a prominent subject when reading the glazing board here, in reality I ave no sense for what will be the better insolator from low / high outdoor temperatures. I guessed that building regs set the levels as low as they have for a reason and so was looking to get close to extension or even new build regs. Any further sense you can talk into me is appreciated. @Mr Punter you would be my builder's best mate to agree 70mm would be sufficient. Our budget is blown to pieces through a very wet start of the year and the virus, is EPS is still a responsible choice for the long term given it's U value, my builder would be enthusiastic take a two day course on it and then try. @Onoff thank you for the post link, I had read it but when i saw the thickness I would need with EPS to get to a U value approaching regs (not that regs are necessary for me as this isn't on the extended part of the house, but still seemed sensible to shoot for that). Maybe falling short, at around 0.38, will still be fine and compliment the plans for 3G and "relative" air tightness around the house. @joth I have no idea. Our roof is being entirely taken off and starting over due to previous poor workmanship. I will be speaking to my builder and read what I can on here about how EMI is managed at the intersetion with roofs. Will also need to see how it is managed with respect to the DPC and around window and doorway returns, I assume it means bringing the frames of these to the edge of the existing blockwork meaning the EWI forms the entirety of returns . @Ferdinand thank you for those remarks. We are going for underfloor insulation and loft, but IWI is less favourable given we have a minimal footprint already. I will look at what thickness of internal insulation would be necessary to get to the equivalent insulation of 70mm EPS or PIR. To all, sincerely appreciate this input, will continue to read other posts, but any more advice would be graciously received.

@PeterW a great price, I offer my sincere thanks!

@canalsiderenovation what did you do for EWI in the end?

Hi all, Major renovation of our 1930s semi-home but will have lots of original external wall retained. Currently have 15mm internal plaster / 215 solid brick / 20mm external render for U-value around 1.8. Builder concerned by prospect of EWI any chunkier than 70mm, (probably to sync with adjoined neighbour / not take up all the soffits overhang / not have windows set undesirably far back) but hopeful I can push him on that. I see that 120mm of PIR would get us down to 0.18, but obviously PIR is phenomenally expensive. 70mm PIR (seems to be max thickness of a single sheet) seems to get us to 0.29. Can anyone steer our thoughts to how to make insulation more affordable, and perhaps what U-value to from a comfort perspective? If PIR is the only option given our thickness restrictions, and we are looking in the territory of 140m2, where will we get access to the best deals? Many thanks

Hi all, Am very close to ordering a whole house MVHR from BPC. As a reminder our project is a renovation, so the retrofit is a challenge. Speaking with my builder, the concessions we would have to make with boxed sections through the main living space, to get MVHR to the further part of the house, is undesirable. I am still seeing what can be done if we use oval pipes, but still it may be very tricky. What are the likely issues I would encounter through having a single room MVHR in that problem far away location, given it would be linked to the rest of the building which is serviced by the whole house MVHR? Will there be additional balancing problems? Or is my only issue the cost of the additional single room unit and having 2 sets of unit filters to manage? Many thanks

Hi all, We need 2 x 2000mm x 1000mm flat skylights for our renovation project. I'm struggling to find the best budget friendly and low maintenance product that will get the job done. £680 exVAT is the best I have been able to find 3G in this size (https://toughenedglasssystems.co.uk/product/skylights-rooflights-1000-1000/ ... yet to determine the Uw in that size), is anything better value out there? Beyond the size, what would you recommend in the battle against solar gain in the summer months? On large flat skylights, should one: - buy with low solar gain glass spec - apply aftermarket external film to reduce gain - combine with external shutter that can close off during period of excessive heat Any advice on what and where to buy is much appreciated.

@Olf Those iris dampers are interesting, thank you for sharing.

@Olf did you make any progress with your potential solutions? As a retrofit project, I'm curious what you settle on.

@bluebirdnick How is your MVHR installation progressing? We have had a provisional design from BPC and seems in the larger rooms they have provisioned for pairs of extract and intake valves (they advise double runs for rooms over 20m2, and double for wet rooms such as bathrooms and kitchens...its essentially double the ducting I expected). Have you paired runs to any rooms? Where have you located your MVHR unit? Our roof is shallow in the loft above the upstairs bathrooms, probably just 0.8m height space, which doesn't seem to be enough for one of these units, especially one where the ducts emerge from out of the top of the unit. It means maybe locating the unit in the main loft above a bedroom, it wouldn't make the duct runs any longer, but worry about noise / vibration in that bedroom. Do you think that should be a concern for us? Did you split your order in the end, or go with BPC? I feel like shopping around for antibacterial and anti static ducting is worth doing to get the best product for the long term. Many thanks

Thanks @tonyshouse, I feel we are on the way to that with planned: Relatively airtight EWI and ceiling / roof more insulated Tinted windows (SKN 176 II most likely St Gobain spec) for east and south elevations External shutters for skylights I can attempt a model, but I'm not particularly handy like that, just about cope with the 3D planner from DIY Kitchen website! It feels like it shouldn't cost lots and be low mess to provision for some kind of active cooling now with ducts or pipes, whether we actually fit any system in say 2 years from now will be determined by the living experience. I cautious as it feels so many builders here say the calcs underestimate overheating, or at least to be comfortable at home, they have ended up needing active cooling despite any calcs prior expecting them to be fine. SO still very interested to hone in on the ideal active cooling solution for budget, effectiveness, and practicality.

I think the only place we wouldn't disturb anyone would be to have any external unit near to the porch area (the link between the garage and the house), but that will draw attention from the street, and could be an eyesore for the driveway area. If anyone thinks that is a suitable location I would be happy to hear that, or alternatives. Reading a post on single room systems, the Olimpia Unico Smart 12HP 9000 looks like a good all in one unit just requiring two holes in the wall. Perhaps one of these in the main downstairs room, and then in the vaulted ceiling area of the upstairs landing with bedroom doors open during the day to get access to that cooling unit. Can a unit such as this have the feed and extract air pipes ran 2.5m over the top of the bathroom, or does it literally have to be on the external wall? The upstairs corridor doesn't have an external wall, although is vaulted so is right near the roof. Honestly I have read tens of posts from the forum on this, and I know a conversion project rather than a new build doesn't have much excitement, but if anyone can advise me at all, I can make a decision on the system, as my builder wants to continue with the first fix next week after the Covid offsite.

Reading more about them, the Olimpia Unico Smart 12HP 9000 seems like a good provision for if an outdoor condenser is too contentious to fit (for aesthetic, PP and likely neighbour reasons). @lizzie did you install one of these units? If so which size, and did it cool the space as hoped based on the evidence from Jeremy. If so perhaps one of these for each of the upstairs and downstairs would be enough provision for my renovation.

@Mike did you look into the water condenser further? It looks like a good concept as external units worry me (planning + neighbours), and are rather ugly. However the water usage does sound enormous, at least air is free with an air to air system.