Redbeard

Hi. Suspended GFs do not always appear to obey the rules of building physics! Having tried on a few occasions to use passive stacks to ventilate sub-floors I think I'd be tempted to add a fan somewhere in your plan (and a sump/drain in case of lots of WV in the 'stack' running back as condensation.

I don't know how renowned the MCS HL calc is for accuracy, but if it is 'within tolerance' and the contractors are quoting to provide 21 degrees to Zone 1 (living room(s) and 18 deg to all other spaces at whatever the low-end assumption is for external temp *without FF bedroom heating* then you are probably OK, and have 'provided (for) heating to those rooms'.

@JamesPa makes a good point. @Rudski, you say: Have you had a full-house heat-loss calc done? If that shows that the proposed provision (with no rads to bedrooms) *will* achieve the 18/21 desired temps in all rooms then I think you have met the requirement which @JamesPa refers to, as long as the quality of workmanship means that the actual meets the plan. If you are relying on a 'gut feeling' then I guess MCS/the installer do not have to have the same gut feeling as you.

''Posted 15 minutes ago (edited) ''@LaChab, Google translate suggests that Rahmenaussenmass means 'external frame dimensions', suggesting (to me...) that that 85mm section is inside. But perhaps I am misunderstanding. Edited 14 minutes ago by Redbeard'' No, I got that completely ar*e-about-face!! @LaChab I think you must be right and I am wrong. So they are inward-opening?

@LaChab, Google translate suggests that Rahmenaussenmass means 'external frame dimensions', suggesting (to me...) that that 85mm section is inside. But perhaps I am misunderstanding.

Ah... Are they inward-opening? I had assumed they were outward-opening, but I cannot find confirmation of that.

Just searched for what KF520s are! Looks enough space there for what I have described but I may be wrong, or you may just like to see a lot more frame than I'm happy with.

I guess it depends how much of the stile you can 'lose'. Usually you can 'lose' up to 20mm without the end result looking stupid. If I had the set-up you have I'd maybe use 2 x 9.5mm plasterboard and once 3mm skim was on you'd have more room for tape.

Most window-taping I have done has been onto the inner face of the window (by less than the depth of the plaster or plasterboard) and thence onto the masonry. It was done after the windows were fitted.

I have seen very poor taping done by contractors and very good taping done by householders. There will also be lots of crossover, of course. Not sure why the Profil would necessarily show on the inside. What shows (or doesn't) depends on the depth of the reveal finish. Pro Clima Profil is designed with a split backing-tape specifically for windows. Equally there is no reason for the split tape if you are good at applying tape, so you can use Tescon Vana or similar from the same manuf'r.

Yes, if there's enough frame left at the top. Look for 'uPVC window repairs' locally and you'll probably find someone who will do it.

SIG group used to sell them, and they have 3 sites in Scotland (not incl. Edinburgh, I am afraid). A search for 'SIG, EPS beads' finds nothing, but it's worth calling them. Good luck.

Try Greenwood Unity CV2SVGIP Low Voltage dMEV Fan I have 3 and rate them highly. Re dehumidifiers, yes, plug-in. Do you have the little boxes filled with absorbent crystals? They are OK for keeping a cupboard fresh (if you remember to change them - note to self!!) but won't do much in a big space.

https://buildingcontrol.bathnes.gov.uk/building-control-services/building-control-fees-and-charges This isn't Yorkshire, of course, but does it shed some light? While searching I see a sugg'n from one firm that private BC can be cheaper but I am not sure that is always the case. Edit: Indeed it isn't: The search brought up only the application fee, not the inspection fee. I have sometimes had a discount from my LA on the 2nd app when I have done 2 together. Your price suggests maybe this has been applied. Assuming they are charging a fee for each extension, rather than one for both, I think your price sounds about right.

Hello! Your thread title refers to Building Regs and you refer in the OP to Planning. The OP seems to suggest that £950 is for planning only. Can you disconfuse me?

I have not used them a great deal, but I have never had any negative experiences with EWI Pro materials (except the hammer-fixings which they supplied 6-7 years ago, which may or may not be the same now - I just routinely go for Ejot fixings now).

Yes, ish... I'd usually get my local wood-wrangler to make me an L-shaped section comprising say 200-300 hardwood for the cill and 150-200 for the presumed soft bottom of the stile. He would do the fancy joint, and I would do my best not to screw up 2 diagonal joints to join new to exg. Or, less 'subtle', and assuming that the 'stop' part of the cill is not badly rotten, just saw/chisel it out square and screw/fill a piece in (bevelling as required for rain run-off), and ditto (less the bevelling!) to as much of the stile as req'd.

Insulation is your best option, as is good ventilation, and depending on your view, PIV might not be 'good ventilation'. There is an argument that, since it has no formal 'outs', it can just push warm, moist air into gaps in the building fabric, where it may condense out. A (still cheap) alternative is decentralised mechanical extract ventilation (dMEV) which uses extract in the wet areas to pull fresh air in through trickle vents in the 'dry' rooms. Internal or external insulation in the long term. Internal more limited re space and re the risk of interstitial condensation (condensation occurring on the old wall behind your new insulation) if you are not v careful. EWI needs careful detailing, possible roof extension and sometimes moving windows/replacing them in a different position in the 'sandwich'. But you can usually insulate more if you do it externally.

Not recently, no. My one experience, with a commercially-available system (can't remember what it was called) was 24-25 years ago and only served to convince me what a good idea rainwater harvesting was! The system (£1000 - £2000 from memory, excluding installation costs) consisted of a rainwater butt sunk in the back yard. Grey water ran to that 'sump', where it was kept from 'fermenting' by 'treatment' - a basket full of chlorine bleach blocks!! . If the contents of the sump did not get used ion 24hrs it got pumped out to the main drain. From this experience I took the view that grey water goes furry, and rainwater doesn't. Simplistic, I know... Low-tech use, perhaps dilute, in garden watering, Grey OK. For storage, maybe not... OTOH over-complicated rainwater harvesting systems can be a right pain!

...quite possibly for less than £1000, OP, if you can send pictures, as previously requested, of the nature and extent of the damage, and words confirming how and when you feel the damage first manifested itself.

+1. Slightly mirrored glass on the outside, PIR and ply to complete the 'sandwich' and then the stud wall seals to the ply.

Well, arguably a window is (of course) a thermal element, but AFAIK it is not a 'Thermal Element' under the Bldg Regs - it is a Controlled fitting. You almost certainly will get Qs re trickle vents but if you can show that you have another supply/extract 'system' (which can be ridiculously simple) you should be able to argue out of this. So no, I don't think you will be required to upgrade the wall in which the window sits. I am almost certain (always allow for a bit of doubt!!) you won't need any paid-for reports. Duty-holder responsibilities are listed here: https://www.gov.uk/guidance/design-and-building-work-meeting-building-requirements The Building Notice form has changed insofar as the client has to sign to say ''I confirm that to the best of my knowledge the work complies with all applicable requirements of the building regulations'', the Principal or sole designer likewise and the Principal or sole contractor ditto. For my last one (renovation of a thermal element) they were all me.

''Means no FENSA cert, but will gloss over that, even with the threat of 2 years jail time under the new regs!'' You don't need a FENSA cert. Apply for a Building Notice, assume and carry out the duty-holder roles and you have BC approval.

Windowsupplydirectltd.co.uk (Malvern): Ray: ray@windowsupplydirectltd.co.uk 07908095493 They will deliver anywhere, as far as I know. They usually (as do others I have come across) make to 36mm, but would be happy to do 44 with the Rehau section.

If it would help I managed to find a supplier who would fit a 'proper' 44mm units (4/16/4/16/4, W/e & 2 x Low E) into a standard Rehau frame (into which most window suppliers will fit 36mm at most. I know Rehau make the requisite bead as they sent me a sample, but the 'DG' world seems to be v comnservative when it comes to 3G. This may all be irrelevant as I'm talking a std Rehau profile which probably isn't I did get a lovely explanation from one (otherwise very good) supplier as to why I could not get a 44mm unit (they *would* give me a 36mm). They patiently explained that the ironmongery they'd use was meant for 2G, and that a 'fatter' 3G unit would be too much... (Ponders the weight of 4mm extra width of separator bar and a bit more argon)