Slim double glazing has been around for a while now and it's prominence within joinery and the construction industry was raised during a 2009 episode of "Grand Designs" on channel 4. If you'd like to see that episode you can view it on channel 4's catch up service here, you'll just have to register before you can view and FFWD to 31:00 to see the section on the windows. We've used slim units over the years and view them as a usefull option for our clients. You can see from the image below how the phrase "slim units" was coined, especially when compared to the standard double glazing unit positioned behind it.
One of the things we appreciate most about slim units is the chance to use completely traditional methods of construction and detailing when the project demands it. This is especially true in respect to glazing bars. With a standard double glazed unit the slimmest glazing bar we can work with is 36mm, and even then, 36mm can sometimes be too slight and on occasion glazing bars can be increaed up to 40mm to 45mm to support and conceal the edges of a standard double glazed unit. You can see below some traditional glazing bar sections, typical of the Georgian and early Victorian period from Peter Nicholson's "<Mechanic's Companion>". We would be able to make all the glazing bars below and glaze them with slim unis, the only change being adding a bit of extra depth to the rebate but no change to the width that is normally around 18mm to 22mm.
As I mentioned, you'll notice I used the word "option" at the start of this write up. The reason is that when it's possible to use standard double glazed units I would always recommend doing so. Standard units are more efficient, better value and easier to get hold of. And even single glazing is still not always such a bad thing. Single glazing can't break down (you'll know if your double glazing is broken down as misty look develops inside the unit) and as long as the pane of glass is not actually broken or shattered it will last forever. Other things to bear in mind are that lead times are longer with slim glazed joinery. Due to the small size of slim units, they require a great deal of hand finishing during the production, this boils down to an extened lead times. Also the glazing takes longer. It is not accpetable to bed any double glazed units into putty, therefore we bed and seal the slim units into their rebates, this is then allowed to cure for 24 hours. We then apply the putty, the putty will then require two weeks to skin before paint can be applied and we would always recommend that paint is applied to the putty before fitting. This creates a lead time from starting the joinery to having it fully painted, ready for fitting of 8 weeks. Once you include the pricing of the job and fitting the overall project time of 9 or 10 weeks from inital inquiry to finished project. There are ways you can reduce the project time, such as not having them painted by us or sorting out your own glazing. However, do be warned, it is our experierience and only our experience that slim units really do benefit from being sent out in fully finished joinery.
So if you do have a project you think slim units might be suitable for please do get in touch, we'd be happy to share our experience with you and provide a proposal for your project 01769 572 134