Sash windows build advice on compliance..

[Ollie78]

If you want replica period sashes then forget double glazing, it's totally incompatible with trad design. Instead look at having internal shutters or secondary glazing, or even just thermal blinds.

It is possible to do a pretty good job of disguising it, it has its limitations of course but most people wouldn't notice until you get less than a meter away.
It's a compromise but can increase the warmth noticeably in conjunction with draughtproofing.

It's not perfect but if you need new sashes anyway then it won't hurt.

Ollie

 

[Ollie78]

Labour council. Hardly describe them as right wing conservatives? They also slapped a Tree Preservation Order on the entire front garden…….which hasn’t any tress in it. In the village another of their imaginative decisions was to slap a local listing on a house that was in the process of combining a cattle shed into it……the shed had and now has to have an asbestos corrugated roof on it. The house roof is now half modern and half corrugated lung disease: you simply can’t make this stuff up.

I worked for a guy in a wonderful old water mill. He had lovingly restored it and I made him a few windows.
They made him keep a corrugated iron roofed coal shed from the 60's.
So I can certainly believe it !!

 

[JC800]

What makes you say this?

Not answering for Ollie.. but to share my one experience with it it stuck well to the knife and stuck well to my fingers but not in the frame. It didn’t take long before resorting to no nonsense belt and braces and did it with milliput. Obviously I’m not pro and I imagine theres a good few reasons it’d be considered awful practice but 3 months in and going strong.

 

[JC800]

Thanks for the input everyone. Sorry I’m a bit late back to resume the discussion. I’ve been told by a few people I should be good to go with making repairs on what I salvaged and keeping them within spec. I’m going to stick with the original glass and thinking I’ll add some strips to extend depth of the casements so’s I can run up to the inner edges with the insulation board then fit the architrave once I’ve skimmed. In theory it seems like a feasible way to improve on heat loss through the weight chambers. Then from there obviously draft proofing, and the insulated blinds recommendation sounds like a good one.

One final thing I wanted to ask.. the windows are made from pitch pine so for sections that need replacing.. what timber should I go with? Can I go with a hard wood or should I just stick to as closer match as possible which I assume will be redwood pine? Whats the done method in that scenario?

Thanks again.
Dave

 

[Ollie78]

Southern yellow pine is a fair choice and not hard to find, you can use reclaimed old pitch pine floorboards if you can find some. Redwood is ok if you can find good stuff.
I always use hardwood for cills, Jewsons stock it in Meranti but they call it door cill.

Ollie

 

[deema]

In Manchester, you should be able to easily find Douglas Fir, and if you feeling flush Accoya which is excellent for window frames too. Personally I would use either Accoya, Oak or Sapele for window cills

 

[Doug71]

Don't want to put a downer on things but I can't see how replacing your existing windows with single glazed ones would comply with the regs, maybe you realise this and are willing to take the risk? It's not just the U values but also things like escape, protection from falling, safety glazing in critical locations etc. You will find single glazing cold if you are used to double glazing.

You could swap them over and all be fine but I would hate to think you went to all that trouble then had to remove them again because of some jobsworth.

 

[HOJ]

I'm afraid I have to Agree with @Doug71.

If I get an inspector who approves repairs then great. Just concerned as they’re salvaged they won’t qualify as the original

Answered you own question really, BC isn't going to help you.

I've been asked to make 10 big windows for a Farm house (existing are far too gone to even consider repair) it's listed, client doesn't want to go down PP route (cant repeat what she said) problem is liability, I'll end up getting prosecuted for doing it, if we get found out, would be a nice job, but I'm not prepared to take the risk.

 

[deema]

@Doug71 @HOJ
The rabbit hole is repair versus replace. My understanding, and I’d really appreciate your perspective, is that repair is allowed, you can actually replace the entire window and frame under repair…..if you don’t agree with the screw definition…..you can replace the frame and refit the original sashes, and then replace the sashes! Now, again it’s my understanding that apart from fitting the correct glass ie safety were required you are not required to under repair to upgrade to the latest standards. Equally, again my understanding, if its listed, even the rules required for safety glass go out of the window (pun intended)

 

[eribaMotters]

What makes you say this?

Getting back to Linseed Oil Putty. It will break down the DG unit. Over 30 years I fitted probably 180-200 DG units in wooden casements and fanlights, softwood and hardwood frames. My method was always the same. Preserve windows and beads with with green Cuprinol, allow to dry thoroughly, use an aluminium oil based primer and then glaze with double sided sticky glazing tape on the vertical rebate with a smear of Butyl putty on the top edge and on the face of the beading where it sits against the GD units inside surface. I've had 3 units break down, so not a bad result.

Colin

 

[Doug71]

@deema there are a lot of grey areas around the regulations for windows as it often comes down to the officer who you speak to on the day. I was once told that a repair over a certain amount (think it was 80%) was classed as a new window but I'm sure there is an argument for the Triggers Broom replacement method.

One of our local inspectors used to be great, he understood older buildings and bespoke joinery, he had the opinion that as long as you were improving things he was happy, unfortunately he has moved on and his replacement is the total opposite wanting every detail and calculation possible to prove that things comply.

 

[JC800]

Don't want to put a downer on things but I can't see how replacing your existing windows with single glazed ones would comply with the regs, maybe you realise this and are willing to take the risk? It's not just the U values but also things like escape, protection from falling, safety glazing in critical locations etc. You will find single glazing cold if you are used to double glazing.

You could swap them over and all be fine but I would hate to think you went to all that trouble then had to remove them again because of some jobsworth.

No downer Doug, I appreciate the input. As it stands I’ve become accustomed to freezing my *** off. I’m on half building site and there are a dozen or so other remedies I need to implement. I dare say if the original sashes went back in tomorrow it would make diddly squat with the absence of the dgu’s. So rejuvenated originals with the rest of the insulation measures in place should be a vast improvement.

The property I salvaged them from was a real time capsule as the previous occupant had been their her whole life. Before it’s new landlord gutted the place I managed to rescue all stained glass, internal doors with all original furnitures still intact. It was the only property with original rear windows along with the stained glass which I also acquired. I even took a moulding from one of the corbels. So I’ve gotten all passionate and insistent upon restoring what’s been gutted from mine. I reckon as I have managed to get the original parts the restoration approach would be a sound investment in terms of financial value also.

Like many others I’m prepared to deal with the shortcomings of original sashes but you’re right. I’m biased towards what I want to hear with no absolute confirmation the positive advice I’ve been given is definitively the correct advice. I guess really I should keep digging before I make a start.

 

[GweithdyDU]

Labour council. Hardly describe them as right wing conservatives? They also slapped a Tree Preservation Order on the entire front garden…….which hasn’t any tress in it. In the village another of their imaginative decisions was to slap a local listing on a house that was in the process of combining a cattle shed into it……the shed had and now has to have an asbestos corrugated roof on it. The house roof is now half modern and half corrugated lung disease: you simply can’t make this stuff up.

"half corrugated lung disease:". My understanding is that the corrugated stuff, which is encased in cement, is not the issue that the stuff used for lagging, and so on is. They still charge a fortune for removing it though!

 

[LBCarpentry]

On a 44 / 45mm sash you can use 16mm heritage double glazing for best effect. 15mm moulding, 2mm butyl tape, 16mm glass and remainder is putty. Approx 10 - 12mm.

Modifying an old sash for larger units has never worked for me tbh. Often the glue has long gone and after bashing them about they are in no state to hold the extra glass weight. It always amazing me how easy old sash’s break apart. They are often only held together by the putty on the glass! Usually one diagonal bash in the floor and the entire thing folds down like a folds thing into 4 neat peices

Quicker and more satisfying to make new ones. Remember to allow for brush seals though.

 

[Jacob]

On a 44 / 45mm sash you can use 16mm heritage double glazing for best effect. 15mm moulding, 2mm butyl tape, 16mm glass and remainder is putty. Approx 10 - 12mm.

Modifying an old sash for larger units has never worked for me tbh. Often the glue has long gone and after bashing them about they are in no state to hold the extra glass weight. It always amazing me how easy old sash’s break apart. They are often only held together by the putty on the glass! Usually one diagonal bash in the floor and the entire thing folds down like a folds thing into 4 neat peices

Quicker and more satisfying to make new ones. Remember to allow for brush seals though.

If you do use brush seals don't put them across horizontally at meeting rails and bottom of bottom sash or you block condensation escape route and create a whole set of new problems.
Sashes work really well as de-humidifiers.

 

[JC800]

On a 44 / 45mm sash you can use 16mm heritage double glazing for best effect. 15mm moulding, 2mm butyl tape, 16mm glass and remainder is putty. Approx 10 - 12mm.

Modifying an old sash for larger units has never worked for me tbh. Often the glue has long gone and after bashing them about they are in no state to hold the extra glass weight. It always amazing me how easy old sash’s break apart. They are often only held together by the putty on the glass! Usually one diagonal bash in the floor and the entire thing folds down like a folds thing into 4 neat peices

Quicker and more satisfying to make new ones. Remember to allow for brush seals though.

Thanks both for the very helpful additional input. I don’t suppose either of you know definitively what the situation is with the legalities. DGU’s were installed sometime in the 80’s (very poorly)…

So with the sash windows being salvaged from another property on the same street, can I replace the DGU’s with restored salvaged units? I understand if the original windows are still in place then maintenance is permissible. But my circumstances differ in that I’m essentially down grading already fitted dgu’s with less energy efficient windows that, albeit match the street spec, are not original to my property. I’ve had a mixed range of answers both on this thread and externally and it’s a big chance to take without the full knowledge applicable to my specific circumstances.

 

[Jacob]

Thanks both for the very helpful additional input. I don’t suppose either of you know definitively what the situation is with the legalities. DGU’s were installed sometime in the 80’s (very poorly)…

So with the sash windows being salvaged from another property on the same street, can I replace the DGU’s with restored salvaged units? I understand if the original windows are still in place then maintenance is permissible. But my circumstances differ in that I’m essentially down grading already fitted dgu’s with less energy efficient windows that, albeit match the street spec, are not original to my property. I’ve had a mixed range of answers both on this thread and externally and it’s a big chance to take without the full knowledge applicable to my specific circumstances.

If it's your own property I'd just go for it. They aren't out there to get you and who is likely to shop you in the first place? In any case you could always retro fit thermal blinds, thick curtains, shutters, etc etc, if called upon.
The only issue is your EPC certificate should you come to sell but replacing DG with other DG isn't going to make any difference

 

[Dibs-h]

If it's your own property I'd just go for it.

I'm with Jacob - I'd just do it.

Replacing some of our ugly uPVC windows with DG sash windows (which I think the house originally had) is on my list of things to make\do. I'll just end up doing it.

 

[JC800]

Thanks both. It seems to be the general consensus so I’m more encouraged to go with it. If the worst case scenario were to happen and Inspector Jobsworth comes knocking to demand their removal I’ll tell him to do one

Cheers all.

 

[LBCarpentry]

I would be very surprised if it would passbuilding regs. Very very surprised