Aluclad windows

decommuter771

Hi,

I have a few quotes in for Aluclad windows on our new house. I've asked for the declaration of performance for each of the windows but I'm not really clear on what basis to assess the quotes (beyond cost, which vary but not wildly across the suppliers).

Any advice on how I read this or what I should be looking out for when reviewing the quotes?

If anyone has any recommendations for a specific supplier, could you PM me please?

Thanks!

fatty pang

The only useful bit of information that is on many DoP’s is the u-value for the window. Apart from that the only other mandatory ‘essential characteristics’ are declarations of dangerous substances and load-bearing capacity of safety devices. You may find the more conscientious manufacturers have data for the other essential characteristics – watertightness, resistance to wind-load, acoustic performance, air permeability & radiation properties.

In the absence of a comprehensive assessment of the window provided by an IAB or BBA Agrement cert you might want to request copies or third-party certification for the window system. Individual test reports are really only indicative of the window that was sent for testing and not of typical production. You might also want to make sure that the certification covers the size of window you are going to purchase – particularly with opening windows that are going to be subject to wear and tear on ironmongery and gaskets.
Warranty – Duration on all components. Parts & labour or parts only.
BCAR compliant supplier - PI Insurance.
Imported or local production – Who will honour the warranty in the event of problems.
Preservative treatment of timber – vacuum impregnated or superficial treatment.
Enhanced security – Secured by Design is standard for UK windows and suppliers here should easily be able to meet the requirement. A worthwhile 'upgrade' that should involve minimal additional cost when installing new windows. (If getting 'European' windows then EN 1629 RC2 should be requested as a minimum)

Good luck – even the professionals often have considerable difficulty understanding window specifications.

decommuter771

Thanks a million!

Would you consider that timber which is dipped is superficial? And is pressure treated similar to vacuum impregnated? I'm trying to relate your comments and advice back to the sales spiels that I've had from each of the vendors!

What difference does it make in terms of lifespan and maintenance of the timber?

If not treated properly, do I risk the timber inside the aluminium cladding rotting or am I just in for a lifetime of maintaining the timber on the inside?

Thanks!!

fatty pang

decommuter771 wrote: »

Would you consider that timber which is dipped is superficial? And is pressure treated similar to vacuum impregnated?

BS 8417: 2011 ‘Preservation of wood. Code of practice’ classes dipping and flow-coating as superficial treatment processes. Pressure treatment typically involves a vacuum process.

decommuter771 wrote: »

What difference does it make in terms of lifespan and maintenance of the timber?

With the preservative penetration provided by vacuum/pressure impregnation of the surface (6mm lateral, x10 end-grain) BS 8417 estimates a minimum service life for external joinery components of 60 years. Other processes are estimated at 30 years. I would stress that preservative treatment although very important is but one factor in the design of windows.

decommuter771 wrote: »

If not treated properly, do I risk the timber inside the aluminium cladding rotting or am I just in for a lifetime of maintaining the timber on the inside?

It depends on the construction. The timber can occasionally be subject to decay if the detailing of the aluminium cladding is poor and the preservative treatment process is not ideal for our climate.

Calahonda52

decommuter771 wrote: »

If not treated properly,
do I risk the timber inside the aluminium cladding rotting

To to add to what FP has said, there is evidence that our very humid , damp climate, especially for north facing windows, contra-indicates Alu Clad.
I have direct experience of this issue in Oregon, where the houses were built in forested areas, with little direct sun and lots of rain, humidity and damp.
The rotting took place behind the Aluclad and the first evidence was when a window slammed shut in a breeze, it kept going and ended in the front garden, whole frame had rotted!

decommuter771 wrote: »

or am I just in for a lifetime of maintaining the timber on the inside?

Thanks!!

What do you mean by this.

I have some Rational type windows and as long as there is no dampness on the windows, there is no maintenance involved: they are that pine look, varnished or whatever from the factory and all I do is look through them, the OH cleans them:D

If you want the alu look outside them go the whole hog and buy Alu frames, thermally broken: end of
I have them also, have just replaced the glazing after 30 years

fatty pang

Calahonda52 wrote: »

To to add to what FP has said, there is evidence that our very humid , damp climate, especially for north facing windows, contra-indicates Alu Clad.

Please don’t conflate what I have written with your half-arsed observations. As I pointed out when you brought this b*ll*x up the first time there are numerous alu-clad constructions.
www.boards.ie/vbulletin/showpost.php?p=94360138&postcount=6

I have some Rational type windows and as long as there is no dampness on the windows, there is no maintenance involved: they are that pine look, varnished or whatever from the factory and all I do is look through them, the OH cleans them:D

Anybody with such a blasé attitude won’t want to be making any claims on the warranty. There is no such thing as a ‘maintenance free’ window. The manufacturer you mention clearly states in their O&M manual “Timber windows need maintenance. This work is limited if maintenance is carried out at the right time…..A crack in the paintwork will allow damp to penetrate the timber, and rot could start.” (they use flow coat system preservative process so have to stress the importance of maintaining the integrity of the protective paint finish)

If you want the alu look outside them go the whole hog and buy Alu frames, thermally broken: end of

Then you have the ‘pleasure’ of aluminium on the inside.

BryanF

Fatty, attack the post not the poster. No more of this please

Self builder Moycullen

Hi all,
I feel into the trap of ordering windows too late and I need to make a decision by this weekend. Can anyone who has ordered aluclad please pm me with what companies you found good. I am getting a lot of conflicting advise.

BryanF

Self builder Moycullen wrote: »

Hi all,
I feel into the trap of ordering windows too late and I need to make a decision by this weekend. Can anyone who has ordered aluclad please pm me with what companies you found good. I am getting a lot of conflicting advise.

There are people who do this type of technical comparison of a living, they way way up technical info like solar gain, heat loss, longevity, warranty, quality, visual appearance, ironmongery etc

Do you have anyone advising on your build you can review this with?