Triple glazing -v- double glazing

polly_selfbuild

Hi, I’m doing a self build and am not sure whether the extra money for triple glazing sliding sash windows is worth it? Has anyone got triple glazed sliding sash and can compare them to double glazed? Research is fairly limited because triple glazed in sliding sash seem to be fairly new.  Thanks for any advice ....

Slithery

You need to compare the difference in capital cost against the projected fuel bills for your anticipated residence of the property. Don't forget to allow for the difference (if any) in the anticipated sale price.

What do your calculations suggest so far?

Awakeatlast

Hi,
I've been in construction for 40 years now. The question you ask isn't very easy to answer. Triple glazing if made to the correct specification will have some advantages. But it will also come with some disadvantages, not least the cost. Triple glazing has better thermal resistance. So it will cost less to heat your new home. But if you have a south facing elevation with many windows on it will also have a greenhouse effect and heat your home in summer. If you want to save money consider the depth and type of insulation you use in the floor, walls and roof space. Your money will return far better when spending in these areas than on triple glazing. Also bear in mind you will have to meet various regulations when installing new windows and often the solutions can look non too pleasing if you are installing sash windows. Check with your architect, if you are using one. Shop around for your quotations too.
 

D.L

Double-double glazing (also known as quadruple glazing) is state-of-the-art nowadays. I wouldn't consider a property without it.

Petriix

It's all about the overall U value of the units including the frames: no point in spending extra on the glass without ensuring the frames are insulated. Double glazing with decent frames will probably suffice, but look at the numbers, not just the number of layers of glass.

Remember that having less (surface area of) glass will be much more thermally efficient than having better insulated windows. If the rest of the house is well enough insulated then you won't necessarily need to worry too much about the windows anyway; look at the overall picture.

greatcrested

I'm not an expert but when I installed new windows and lookd into this the general concensus was that  the additional benefit was marginal as against the higher price. If living in Scandavia or somewhere really really cold it's apparantly worth it...

princeofpounds

The U value of a high quality double glazing unit (e.g. argon gas filler, low e coating etc.) is often better than regular triple glazing. Just to illustrate why layers of glass is not always the main thing. Like many things it's diminishing returns - moving from single to double is much more important than moving from double to triple.

Triple glazing doesn't really make financial sense - typically figures around a 5% improvement in energy efficiency in the house tend to be given. That's what, £60 quid a year? Not a great payback on the capital cost - other improvements would do more for you for the same cost. However, if you are building some luxury into a house, the extra sound-deadening and reduction of temperature differentials within rooms may be something that appeals.

They are necessary to meet 'passivhaus' standards, but let's be clear - buildings like that are luxury products.

martindow

What about accoustic insulation?  Presumably the extra pane would help if you lived near an airport or main road helping to justtify the extra expense beyond the savings in heating costs.