Window schedule for Passive House - Presenting the info to receive quotes

[Furnace]

In order to avoid endless tail chasing when seeking quotes, I'm keen to present all the information required so quotes can be fairly compared.
Having read the sticky, I've put together the 2 attached docs.
window_schedule_plans.pdfwindow_schedule.pdf

I also need to add:

• Gas filled
• Any coatings
• Glazing build-up (e.g. 4-16-4-16-4)
• Aluclad, aluminium or wood.
• Inward/outward/tilt'n'turn
• Delivery and installation
• Number of compression seals (particularly on the weather side of the locking mechanism)

I'm inclined to go Aluclad, but have not particular view on the other choices. I've only encountered inward/tilty jobs when in Europe and have no experience of 'living' with them.

As an aside, I'm curious about some windows that don't have a compression seal on the weather side of the locking mechanism. This seems a bit daft to me?

All suggestions most welcome.

Edited April 3, 2023 by Furnace
added question

[MikeSharp01]

What you have looks good, you need to give them enough so that they can get it right first time rather than change things when they find out that your openings are not what they assumed in terms of build up. So other things to think about including are:

• Making sure the quote contains the Uw values for every window - you need to meet PH standard there.
• Specifying if the installer is responsible for attaching air tight membrane tape and / or connecting to the airtight layer adjacent to the window.
• Which windows are designated escape windows, if any.
• Which door(s) is(are) your accessible door(s) for BC purposes.
• If you have section drawings of your openings that will help them, and stop them coming back and upping the quote when they find a difficult opening.
• Including / not including such things as compriband on the external connection to the opening.
• Which foam to use when sealing around the windows - You can say a brand and /or say it should have similar properties to a brand.
• The finished colour(s) inside and out (Some colours are standard others cost), also if coastal location you will need a marine grade finish.
• Do you want secured by design as standard on all doors / windows on GF - this affects the glass build up and the locking.
• If you are expecting the windows to be installed with access to both sides. IE will they work from the inside or both sides. (On ours the windows are bigger in their boxes than the surrounding tile hanging so they need to go in from the inside although you can work on the outside.) Section drawings will show this to them.
• What is access like to the the site - can they get a lorry close and / or a window robot around all sides.
• Is there / will there be scaffolding - window robot then no good. 

Hope that helps.

[nod]

You need to get them to stick to YOUR numbering Window suppers have a habit of adding there own numbering or get to say window 5 and put x 2 

Looks crystal clear to me 

[Bitpipe]

We had the debate between frame and window supplier of 'who owns the tolerances?' i.e if the aperture and window are exactly the same size then they won't be installable - one party or the other needs to allow  5mm all round and compriband & tape will take care of making everything airtight post install.

 

Also, if it's a supply and install package (which I'd insist on), make sure that any plant required by the window supplier is either specced or is part of their quote. We had some confusion over who was paying for the telehandler at the 11th hour.

 

 

[AppleDown]

7 minutes ago, Bitpipe said:

We had the debate between frame and window supplier of 'who owns the tolerances?' i.e if the aperture and window are exactly the same size then they won't be installable - one party or the other needs to allow  5mm all round and compriband & tape will take care of making everything airtight post install.

 

Also, if it's a supply and install package (which I'd insist on), make sure that any plant required by the window supplier is either specced or is part of their quote. We had some confusion over who was paying for the telehandler at the 11th hour.

 

 

Out of interest who did you end up going with? Trying to collate a few shortlists for different jobs, and in your area. Thanks!

[Bitpipe]

This was a while back (2016) but we used MBC for the passive frame and Gaulhofer (via EcoWin @craig) for the passive windows.

 

Very impressed with both firms, can't recall who ate the tolerance in the end, think it was Gaulhofer

 

The golden rule here is to double, and then triple check all window schedules before committing.

 

Errors can creep in, even with the best supplier as the s/w they have to use to order from the manufacturer can be painful and can reset previously selected options etc.

 

Even then, errors may be made at the factory but as long as your schedule is clean then you'll be able to get them to resolve it at their expense.

 

I fkd up our door order from RK Doors - fit fine but the ratio of door to glass was off and I didn't spot the mistake so had to live with it.

[Furnace]

4 hours ago, MikeSharp01 said:

Hope that helps.

Thanks Mike. All excellent points.

 

[Furnace]

3 hours ago, nod said:

You need to get them to stick to YOUR numbering Window

I've found it difficult enough to keep track using only MY scheme!

[craig]

An excel sheet with the sizes quantities and types is usually good enough, window schedules are usually best and take away any ambiguity. If you can also specify what windows are below 800mm from FFL that will help, with any specific security requirements (i.e. SBD/Pas24, Emergency escape windows). The one thing to look out for with your quote is glazing (especially triple). Look out for the middle pane of glass being float glass and those that toughen the middle pane (more so on South East to South West windows). 

 

We did this with one of our suppliers for a while to match everyone else's price as it's very competitive and to be honest, you all like to do cost comparisons on m2 prices and it can be the difference between winning or losing a job. However, it's important to note that this is the number one way to save costs but it can cost you in the long term if it breaks (whether that be from slamming shut, thermal stress, or thermal fractures) the bill for this is left with you. We always did this with our Austrian supplier but not with our other suppliers - a lesson has been learnt.

[Furnace]

2 hours ago, craig said:

Look out for the middle pane of glass being float glass and those that toughen the middle pane

Not sure I understand. I'd imagined that glazing below 800mm needed to be toughened (inner pane only?), but all other glazing would be float. If any glazing breaks, surely that's my problem? Am I being dim?
 

edit
Is it that the centre pane of all TG units should be toughened because it's subject to greater thermal stress and therefore more vulnerable?

Edited April 3, 2023 by Furnace

[craig]

Safety glazing should be inner and outer, no current regs re triple glazing.

 

Yes, regarding middle pane and thermal stress. 

[Gill]

I'd add any acoustic requirements to the list and get the acoustic performance included in any quotes. 

 

I didn't pay enough attention to that and it's the one thing that irks me post install. 

[Furnace]

30 minutes ago, craig said:

Safety glazing should be inner and outer, no current regs re triple glazing.

 

Yes, regarding middle pane and thermal stress

Gotcha. I didn't know that, so thanks.
Do the windows next to the doors need at least one laminated pane to comply with PAS24? Do 'normal' windows in situations where they're not next to doors typically comply with PAS24? Any other requirements that might trip me up?
Cheers

[Furnace]

28 minutes ago, Gill said:

I didn't pay enough attention to that and it's the one thing that irks me post install. 

Gilly,
Are yours double or triple? I haven't looked at acoustic specs, and dumbly assumed TG would be 'pretty quiet'.

[Gill]

2 minutes ago, Furnace said:

Gilly,
Are yours double or triple? I haven't looked at acoustic specs, and dumbly assumed TG would be 'pretty quiet'.

Triple. I assumed the same but looking retrospectively there are DGs that give the similar values to my TG and alternative TG that have better acoustic performance. 

They are a vast improvement on our previous but I think I expected better and should put more weight on that requirement as we're near a busy road and have loads of seriously noisy birds nesting in the hedge! 

[Furnace]

@craigIs this the sort of thing that would make comparison easier and avoid to-ing anfd fro-ing? I'd also say I'd like a 'supply and fit' quote inclusive of fitting materials. Does that make sense?

[Furnace]

11 minutes ago, Gill said:

alternative TG that have better acoustic performance.

Gotcha. Do you mind sharing the make you went for so I can stalk the acoustic data as a reference? I currently have single glazing (listed gaff) so anything will be an improvement, but there's no reason not to perform due diligence with  clean sheet of paper at hand.
Cheers
M

[Gill]

@Furnacewent with Senior Architectural Systems Pure. I think acoustic performance is a bit like u value in that you need to consider both the glass and the frame but someone more knowledgeable that me will hopefully confirm if I'm talking nonsense or not. Overall we were given a figure of 39 dB and u Value . 95. 

 

The other thing that comes to mind purely based on my experience is I specified no trickle vents. Didn't want any more ventilation than we already have. Was reminded it would be a sell on issue without alternative ventilation installed but in my limited experience, trickle vents were assumed unless you specified otherwise. 

 

[Furnace]

Good point. I'm going Passive House and MVHR so trickles not wanted but I need to remember to ensure they're not automatically included.

[craig]

2 hours ago, Furnace said:

@craigIs this the sort of thing that would make comparison easier and avoid to-ing anfd fro-ing? I'd also say I'd like a 'supply and fit' quote inclusive of fitting materials. Does that make sense?

Looks good to me 👍

[craig]

2 hours ago, Gill said:

I think acoustic performance is a bit like u value in that you need to consider both the glass and the frame but someone more knowledgeable that me will hopefully confirm if I'm talking nonsense or not. Overall we were given a figure of 39 dB and u Value . 95. 

To much emphasis is placed on the acoustic values and it’s generally the glass that is rated and not the unit. That being said, most ignore the most important aspect. That is how sound travels.

 

Sound is like water, it’ll find a way. That’s why a very important factor is how the window is installed and the materials used. If they just used PU foam for example, that will have lots of pockets of air. Having the outside aspects around the window filled with a Compriband seriously reduces the noise levels. Noise doesn’t just travel through the window but around the window.

 

Noise will also travel through the ground and up through the floor and through walls etc. Very good idea to get a good dB level of glass but installation of that unit is paramount to it’s success.

 

 

Edited April 3, 2023 by craig

[craig]

3 hours ago, Furnace said:

Gotcha. I didn't know that, so thanks.
Do the windows next to the doors need at least one laminated pane to comply with PAS24? Do 'normal' windows in situations where they're not next to doors typically comply with PAS24? Any other requirements that might trip me up?
Cheers

Anything with 300mm of a door should be. However, Pas 24 will generally be all ground floor windows and any that are easily accessible from ground.

[craig]

11 hours ago, Bitpipe said:

think it was Gaulhofer

With MBC, they generally eat the tolerance but not always. Sometimes we will with MBC. Most others it will need to be us that eat the tolerance.