Increasing glass thickness in sash windows to reduce noise.

[chainsaw_masochist]

Some friends in a flat with secondary double-glazing find accessing the main sash window a bit of a pain. They are curious to know whether replacing the existing glass in the sashes with thicker equivalent glass would improve the sound proofing to the extent that they could ditch the secondary d-g. They are three floors up from a main road. Does this sound workable?

Thanks for any advice.

 

[HERTS P&D]

In a word, NO.

The sashes are weighted with the glass so that they can be lifted up and down, any thicker glass would not make any difference.

Keep the secondary glassing.

Andy

 

[Sam777]

I have in the last 12 months had a joiner in reconditioning upwards of 30 sash windows in our property. Some of the sash's were rotten so they had to be replaced. The new sash windows were installed with DG units and the rest had the single glazing retained. The external noise levels from the DG units are noticeably lower than the single pain. So yes DG/thicker glass will make a difference. However, it is unlikely that the profile of the existing sash's will easily allow for a DG unit to be installed. So I would argue DG glass will reduce noise but they will more than likely have to replace the sash's and the weights - this is probably cost prohibitive unless the windows are in a poor state of repair and would benefit from it. To be honest keeping the secondary glazing is likely to be there best option and whilst DG is better at reducing noise than a single pane the secondary glazing is more than likely more effective than a DG unit!!

 

[Deleted member 174758]

So yes DG/thicker glass will make a difference. However, it is unlikely that the profile of the existing sash's will easily allow for a DG unit to be installed.

The very thinnest DG units are something like 11mm (4 / 4 / 3 Argon filled) whereeas window glass may well be just 4mm thick. Few sashes have an extra 7mm to play with. The other thing which has to be taken into account is the extra weight of DG units. It just may not be physically possible to incorporate the larger weights in the sash weight boxes needed to counterbalance DG units

 

[Sam777]

So yes DG/thicker glass will make a difference. However, it is unlikely that the profile of the existing sash's will easily allow for a DG unit to be installed.

The very thinnest DG units are something like 11mm (4 / 4 / 3 Argon filled) whereeas window glass may well be just 4mm thick. Few sashes have an extra 7mm to play with. The other thing which has to be taken into account is the extra weight of DG units. It just may not be physically possible to incorporate the larger weights in the sash weight boxes needed to counterbalance DG units

Yep all valid points but as I mentioned it can be done as my windows go to prove. My original frames were kept and we added extra weight to the original so they are slightly longer. Windows still fully open and aren't affected by extra length of weight. At the end of the day a good joiner will need to see them and advise.

 

[chainsaw_masochist]

Thanks very much for all of your very helpful comments.

 

[PBSCO]

Having the sashes draught proofed will decrease the noise more than having thicker glass.
Plus it will help with heating and dust and dirt coming through the gaps all around the windows.
Quicker to do the draught proofing as well,as changing the glass will mean having to wait at least a week for putty to dry before painting.