Hello, I wondered if anyone can help. My partner and I have recently bought our first home together on the Forest Hill/Sydenham border. Over the winter our new flat was freezing even with the heating on full blast. We have 6 very draughty single glazed sash windows, including a large bay window at the front of the property.
My question is… do you think we should replace the windows entirely with new double glazed windows, or can we make it warm by renovating the existing sash windows? We don’t have loads of money. It would be great to hear from other locals living in period properties and find out how you have dealt with this issue.
I have 4 large single-glazed sash windows in my flat which were very draughty. If the wind was in the west, I could see my curtains flutter in the breeze.
I chose to get mine renovated but be warned, it’s not cheap. Admittedly, I had a couple of really dodgy frames, one of which had the bottom sash remade. I also got them draught proofed and it made a huge difference. The expanse of glass can still be chilly so some lined curtains also make a difference. I can’t recall exactly how much it was - but I think it was around £2k. I was recommended the Sash Guy via the East Dulwich Forum and he was very good.
Bear in mind that you can’t simply change existing sash windows into double-glazed ones. Because sash windows are balanced with their weights, double glazed ones would be too heavy for the current weights so you’d also have to pay for new weights. I seem to recall that entirely refitting them to double glazing was going to be 2-3 times the price.
I also seem to recall that renovating existing ones doesn’t require building control whereas replacement ones might? Double glazing ones can be easier to open/clean but might also depend on what your neighbours have and whether you need them for noise reduction as well as heat retention.
I have installed the storm guard brush seals that are brush seals and allow the sash windows to slide. This is the cheapest option and does help with some of the draught but you will still get the cold transfer through the glass. We have painted our sash windows shut on the ground floor that also is a security measure and sorts the drafts - we would never open them anyway as we have enough air circulation from open floorboards. The double glazed pvc sash windows with run through horns and heritage features are now really good and hard to tell the difference from a distance and given the maintenance savings this is our plan in a few years - they are expensive. I have taken out the sash windows and refurbished them on the first floor that is not too difficult but time consuming as you need to put them back in between coats etc. However it does mean that you can paint them and the frames without a ladder as once the sash parts are out it gives great access to paint the outside frames from within. We have installed shutters inside and it does keep it slightly warmer when closed but again not cheap. Planning is always required for a flat to change windows as no permitted development rights exception and a house depends on whether it is in a conservation area but best to check with Lewisham planning.
The previous owners of our house installed internal secondary glazing. Ugly buy very effective. Also surprisingly effective is the plastic film where you tape over the window frame and use a hair dryer to make it shrink to fit. We did this a few times on windows we knew we wouldn’t need to open. But you have to make sure there is other ventilation.
When we came sort out the windows, we did a mix of refurb and replacement. We also used The Sash Guy from East Dulwich and would recommend him. We only refurbed and brush sealed windows that were in reasonably good nick. With the replacement ones we didn’t need any building control because we were replacing the sash unit inside the window frame and didn’t remove or replace the frames themselves. We put in double-glazed unit and as noted about, the new lead weights add a lot to the cost of these.
I used to live in a very similar house in FH and had the same issues. I used secondary glazing plastic film, available form Homebase, B&Q etc. Was amazed at the difference for the sake of around £16. Once on you barely register it is their. Also reduced outside noise quite a bit.
If you are, unfortunately, the Council’s attitude towards UPVC replacement windows is completely backward, given that there are some very good manufacturers who make sash windows with the correct proportions and through-horns etc and which are waaaaaaaay cheaper than wooden replacements - or refurbishment of old originals.
To give you some example - even though you won’t see the horns, which are external -
This window is 3 units joined together so it was priced accordingly, however, the centre unit is 7 feet tall and 3 feet wide and it cost £380. It has 25mm argon-filled double-glazing and the sashes are tilt and slide. Importantly, the lower sash has a deep bottom rail, which is critical in terms of aesthetics.
So, if you’re outside the Consevation Area - BINGO!
Sorry @DevonishForester , I’ve had a good look on Lewisham’s planning pages but I can’t find it. I’m sure it used to be on there. I’ll have a dig through my old paperwork to see if I’ve still got a hard copy that I printed-off a few years ago.
Lewisham’s rigid wooden-over-UPVC argument was, I’m sure, based upon seeing some poor attempts at replicating the essential look and aesthetics of an old window but all UPVC sliding sash windows are not the same!
I think he might be the same person as colinssashwindows.co.uk. I spoke to him on the phone and his prices are great. The windows are synseal evolve. My builder recently fitted 4 for me, purchased from fascia place, but I intend to buy more from this chap.
Good idea. Perhaps we could add a heading to the recommendations page for general “neighbourly advice” topics like this.
You should be technically able to edit the recommendations page yourself (it’s a wiki topic) and I’d encourage established members to do so. Only condition is that the topics listed there are for general recommendation lists, as opposed to recommendations for individual companies.
Yes, there are some excellent UPVC sash replacements. I would be interested to hear from anyone in the conservation area who has navigated this with Lewisham Planning.
Perhaps the insistence on wooden sash replacement should be assisted with a grant?
As modern sash windows are excellent replicas, coupled with ease of cleaning and sound and heat insulation. Difficult but surely conservation of energy trumps draughts and maintenance and without a trained eye no apparent difference.
I should add that some changes are ridiculous with outward openings and ‘georgian’ panels and certainly see a point of view where totally incongruous windows are fitted. Maybe the planners should have a recommended design/supplier?
I agree with you @Wynell .
On the planning part, at least their guidelines should stipulate minimum ‘heritage’ design features such as ovolo glazing bars, deep bottom rails and run-through horns?
Thank you @Sandinista, this document is the one I was looking for - but it really winds me up!
Yes, in an ideal world (where slow-grown softwood and craftsmanship cost the same, relatively speaking, as it did back in the early-1900s) people would all be able to afford to do like-for-like replacements - but they can’t. So, as preserving the look and the character of an area can essentially be achieved by using a modern, less-expensive material and manufacturing process, I find it really annoying that many local authorities are still digging their heels in on this.
