Any advantage of replacing entire window unit over just the panes?

Ben1989

Hi all,

I have condensation in our corner bedroom and condensation on the window and inside the window.

It's a corner window (i.e. two sides at right-angles). One side joins the gable wall which is single-brick and the other on the front cavity wall.

So, we're looking at replacing the window to improve heat in the room. We also have mould issues in there. Just trying to knock down improvements one by one.

I know nothing about windows hence why I'm writing this post. Is there any benefit from replacing the entire unit (i.e. frame) rather than just the panes? In what circumstance would you replace the frame?

Bendy_House

Usually only if: they are worn, poorly sealing, sticky, don't open and shut fully, have gaps, or have been badly fitted from the off.
Or, if they are of a inherently poor design - no proper thermal break, thin frame depth, etc.
Or, if they look carp.

Replacing just the DG units should be a LOT cheaper, so the additional cost of complete replacement would really need to be justifiable.
I suspect that the mould issues in the bedroom are not due to these windows (unless they are actually letting in water?), so don't be upset if replacing them doesn't fix the problem.
For instance, a 'blown' DG unit retains almost all of its insulation properties. 

Bendy_House

Photos of the condensation and mould?

shiraz99

Ben1989 said:

Hi all,

I have condensation in our corner bedroom and condensation on the window and inside the window.

It's a corner window (i.e. two sides at right-angles). One side joins the gable wall which is single-brick and the other on the front cavity wall.

So, we're looking at replacing the window to improve heat in the room. We also have mould issues in there. Just trying to knock down improvements one by one.

I know nothing about windows hence why I'm writing this post. Is there any benefit from replacing the entire unit (i.e. frame) rather than just the panes? In what circumstance would you replace the frame?

I'd only replace the whole window if the frame itself is looking tired, or damaged. If there's nothing wrong with it then just replace the blown glazing units. The difference in cost is between a couple of hundred for the units compared with £1K plus for a new window.

TELLIT01

If the windows are very old, there may be a benefit in replacing the entire frame, because newer windows tend to have a larger gap between panes and are therefore more efficient.  That said, the savings will be tiny in comparison to the cost of replacing the entire window.

[Deleted User]

Hi,

and to save even more money you could diy.

Buy your units locally and fit yourself, VIDEO.

FreeBear

Bendy_House said:  Replacing just the DG units should be a LOT cheaper, so the additional cost of complete replacement would really need to be justifiable.

This is assuming the windows are double glazed.

Old single glazed windows, I would be looking at replacing with double or even triple glazed, frames & all. New Building Regulation guidance comes into force from June 15th which requires (slightly) higher thermal performance plus background ventilation (either trickle vents or PIV).

Ben1989

So, we had someone around this morning to take a look.

He said the window is completely cheap and actually contained zero insulation. (it was graded F). He said with it due to being an (older) corner window it contains silver in the join which was literally freezing.

He said replacing the panes will essentially just make the window look fresher with very minor thermal improvement. He pointed out mould on the window which we never noticed and explained it essentially will never go away with a pane replacement. 

He suggests replacing with an A-rated window & frame which should significantly improve the thermal properties of the room. (it's freezing compared to the rest of the house).

I know it's obviously salesman spiel but we have dealt with this company before and the guy seemed transparent and has always gone above and beyond.

He's going to quote us later so see what prices he comes back with. 

We're likely to go ahead with full replacement as our 1 year old will be sleeping in there in a matter of months and don't want her freezing and breathing in potential mould.

twopenny

Be aware that the grading has decent changed.
Looking at freezers the other day they were all F where they had been A or B. Seems another one of the'take advantage of covid' things. 
It could be that person was mixing with the new regs. Maybe real.
If the condensation is in between double glazing panes you can have them fixed or just the glass unit replaced by a window doctor.
If there's mould in the room it could be just ventilation. You aren't airing it enough. Sounds like it's been left unused.

greenface2

Glass has improved more than frames with insulation . stopping the cold entering is the aim but getting enough ventilation to stop the damp and mould forming is the other . The salesman isn't wrong and maybe making all the right noises . frames have improved . wider chambers . thermal breaks . multi gasket . improved locks . better drainage . trickle vents optional for now but not soon . a good decent fitted a rated frame with argon or planitherm glazing would increase the thermal values of your window . then you can tackle the single wall and cavities . wooden floor / loft insulation ect . wall vents

FreeBear

greenface2 said:. trickle vents optional for now but not soon .

Latest version of Building Regulations, Part F requires background ventilators to be fitted in habitable rooms, with a minimum of four in a one bedroom property, and five in all others. The regulations only define a background ventilator as "a small ventilation opening designed to provide controllable whole dwelling ventilation". It does not say "trickle vent", so if you have other means of providing this background ventilation, trickle vents can be omitted.