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Off the shelf non vented roof windows

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I have 3 roof windows, all of opening size 895 x 1145 and they need to be non-vented.  My roofer has sourced some, but says that they are made to order and the lead time is 15 - 21 days; I'm not sure yet whether this is calendar or working days.  Either way, I would ideally like to get some sooner than this as it's highly likely that they won't be in before the due date of my air test.

 

Does anyone know of a source for these that are off the shelf or have a shorter lead time?

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Non vented, non opening or both ..?? 

 

Fakro do them but I think they have to be non-opening too

 

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I don't mind whether they are opening or not as I don't plan to open them, but they definitely have to be non-vented.  I've had a look at plenty of suppliers on the web, but I think I will struggle to get the size I need as an off the shelf item.  Hey ho, you can't win them all.  I'll stick with my roofer's option and hope that they arrive in time.

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can't you just keep the vent closed?

 

can you change to a more common size?

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1 hour ago, dpmiller said:

can't you just keep the vent closed?

 

can you change to a more common size?

 

 

The problem with that is that the closed vents aren't really airtight, plus they form a nasty thermal bridge through the frame, and on a roof light in a passive standard house they will almost certainly attract condensation.

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I am still needing two. Every house I have yet seen, including those with mvhr and no ordinary window vents, still has vents in the roof windows.  I honestly didn't think you could buy them without. Can someone point me to details of ventless, but opening 3G roof windows please?

 

And tell me how much extra you have to pay for not having a vent fitted. :ph34r:

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1 hour ago, ProDave said:

I am still needing two. Every house I have yet seen, including those with mvhr and no ordinary window vents, still has vents in the roof windows.  I honestly didn't think you could buy them without. Can someone point me to details of ventless, but opening 3G roof windows please?

 

And tell me how much extra you have to pay for not having a vent fitted. :ph34r:

https://www.fakro.co.uk/products/all-products/roof-windows/centre-pivot/

Those are ours with 3g and low transmittance glass. I don't know the cost of ours as it was lumped in the the frame cost.

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My house is currently specced as Velux but I looked into changing to Fakro to get rid of the vents. But AFAICS you could get them without vents but only on the lower spec 2G windows which seems back-to-front, it's people who're buying the higher spec windows who'd want to leave it to the MVHR. E.g., on the page @PeterStarck links to the only variant without the vent is the FTP R1 which is 2G 1.3 W/m²K as opposed to the FTP-V P5 which 3G 0.97 W/m²K with the vent. Or can you specify FTP P5 (without the “-V”), and get triple glazing without the vent, even though that's not listed there?

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44 minutes ago, Ed Davies said:

My house is currently specced as Velux but I looked into changing to Fakro to get rid of the vents. But AFAICS you could get them without vents but only on the lower spec 2G windows which seems back-to-front, it's people who're buying the higher spec windows who'd want to leave it to the MVHR. E.g., on the page @PeterStarck links to the only variant without the vent is the FTP R1 which is 2G 1.3 W/m²K as opposed to the FTP-V P5 which 3G 0.97 W/m²K with the vent. Or can you specify FTP P5 (without the “-V”), and get triple glazing without the vent, even though that's not listed there?

I don't have any separate record of the roof window details so I've looked back through my PHPP data and it is a FTT with 3g and clear reflective outer glass. It looks like it's a U6 but they may have changed the spec. as mine was bought in 2010.

https://www.fakro.co.uk/products/all-products/roof-windows/highly-energy-efficient-windows/#

Sorry for the confusion.

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The ones that have been sourced by my roofer are only 2G and have a uW of, I think, 1.3 without looking back at the quote.  The supply and install cost per window is £498 plus £72 for each flashing kit.

 

The uW value is higher than I would like, but I can live with it on the basis that the large triple glazed windows in the house have uW values of about 1.2.

 

I went through an online quote system on one of the websites this morning for passive roof windows and they came out at about £1500 each just for the window.  So, for a total of 3 windows with fitting and all the kit, I reckon I would be looking at about £5k+ all in.  The difference of £3500 can buy a lot of heat and I'm not sure that the extra cost for 3G is worth it for me.

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This is the topic I was looking for , I am going to ask this in Builders Forum as well, as many of you are not specific experts, but maybe someone might know.

Same problem with the rooflights here:

I need Unvented Rooflights/Windows. Would like them Non-openable since that seems to better U value and mine are around 6 meters up, so would never be able to open them anyways.

America does some great, cheap windows . Since their Houses are Airconditioned they do Velux ones as a standard 1146455597_FSSizesS06andSmallerwith04Glazing111717.thumb.jpg.538904c0d06477d61aa33a474ec2ef17.jpg

 

You can find them here for example:

 

https://www.ebay.com/itm/Velux-FS-C04-2005-21-1-2-Inch-x-38-3-8-Inch-Tempered-Fixed-Non-Vented-Deck-Mount/382780188537?epid=17012067669&hash=item591f7a2779:g:RCUAAOSwuFZcYODr:rk:7:pf:0

 

Now the whole importing from US process puts me off a bit , but they are much better and much cheaper then all the Fakro offers and also much better (For this purpose) than the UK Velux windows that open.

 

Now finally the question:

 

I had some Flatroof Roofligh manufacturers claiming that it was absolute no problem installing Flatroof lights (which also have fairly decent U value)

into a pitched roof (mine is 34 degrees)

 

Panoroof1-2.jpg.98ae36587a0929e132aa54f9358a8f9f.jpg

 

https://www.panoroof.co.uk/product/600mm-x-1200mm-triple-glazed-skylight/

 

 

Now i do not know if this is just Salesmen talk or if it can be done without a problem.

Any Window Installers or Roofers on here?

 

Please enlighten me

 

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That U value looks pretty grim to me, 2.49 W/m².K?  UK building regs minimum fabric standard is 2.00 W/m².K, and that's not exactly great, either.

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@JSHarris ok, did i missread this? I thought the U value was  0.44 and the 2.49 was the R-Value. bit confusing to me

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just had a look at the email from Velux :

 

Good morning Patrick,

 

VELUX FS model (or deck mounted) skylights with laminated glass will have a U-Factor of .44 and a SHGC of .26

 

VELUX FCM (or curb mounted) skylights with laminated glass will have a U-Factor of .48 and a SHGC of .27

 

I have added the energy efficiency info (as well as installation instructions) to this reply so that you can look this over and determine which would be more appropriate for your application.

 

Please let us know if we can help you further.

 

 

With kind regards,

 

VELUX America LLC

Business Services

www.veluxusa.com

 

 

.

 

Is the U-Factor the U-Value ?

 

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The 0.44 us an imperial measure in unspecified units.

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3 hours ago, Patrick said:

@JSHarris ok, did i missread this? I thought the U value was  0.44 and the 2.49 was the R-Value. bit confusing to me

 

 

I read that as being the US (Imperial units) U value = 0.44 BTU/ft².°F and the metric U value as being 2.49 W/m².K

 

If 0.44 was the metric R value, then the U value would be 2.27 W/m².K

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If thats correct, then these windows are   "out the window"  😁

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Fakro do PH certified rooflights, that have U values ranging from 0.58 W/m².K to 0.81 W/m².K, so a heck of a lot better than the US Velux ones.

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Yes, thats true, I was misreading the whole conversation as "U-Value is 0.44" and thought AMAZING.  

Then it s only a question about wether I can use Flatroof skylights or not.

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3 hours ago, JSHarris said:

U value = 0.44 BTU/ft².°F and the metric U value as being 2.49 W/m².K

 

That is, at least, consistent: 2.49 W/m²·K = 0.438537… BTU/h·ft²·°F.

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Velux don't do unvented, Fakro do. Infuriatingly this drives the price up considerably. Beers Building Supplies have offered a decent discount off Fakro RRP, so perhaps try them. I'm afraid the lead-in time won't change though. They suggested 21 days for unvented as this is a special order product, whereas they have thousands of vented ones on the shelf, which can be dispatched immediately.

 

For the u-value debate (if this is of any use to anyone) on 118x78cm rooflights we're looking at a u-value of 0.97w/m2k (centre pane value 0.5w/m2k) for triple glazed and 1.3w2K (glass u-value 1.0W.m2K) on double glazed, the latter of which is probably the option we'll end up with.

 

I don't know what they're like, but have just come across YARDLITE unvented off the peg rooflights with delivery in 3-5 days and a next day option available. https://www.yarddirect.com/yardlite-aax-centre-pivot-unvented-white-pine-roof-window I wonder if anyone has used this brand before and can vouch for it?

 

Edited by laurenco
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On 21/02/2019 at 18:06, laurenco said:

Velux don't do unvented, Fakro do. Infuriatingly this drives the price up considerably. Beers Building Supplies have offered a decent discount off Fakro RRP, so perhaps try them. I'm afraid the lead-in time won't change though. They suggested 21 days for unvented as this is a special order product, whereas they have thousands of vented ones on the shelf, which can be dispatched immediately.

 

For the u-value debate (if this is of any use to anyone) on 118x78cm rooflights we're looking at a u-value of 0.97w/m2k (centre pane value 0.5w/m2k) for triple glazed and 1.3w2K (glass u-value 1.0W.m2K) on double glazed, the latter of which is probably the option we'll end up with.

 

I don't know what they're like, but have just come across YARDLITE unvented off the peg rooflights with delivery in 3-5 days and a next day option available. https://www.yarddirect.com/yardlite-aax-centre-pivot-unvented-white-pine-roof-window I wonder if anyone has used this brand before and can vouch for it?

 

NOW this is what I call usefull Inforamtion ! Thanks .

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On 18/02/2019 at 17:11, Patrick said:

I had some Flatroof Roofligh manufacturers claiming that it was absolute no problem installing Flatroof lights (which also have fairly decent U value)

into a pitched roof (mine is 34 degrees)

 

Panoroof1-2.jpg.98ae36587a0929e132aa54f9358a8f9f.jpg

 

https://www.panoroof.co.uk/product/600mm-x-1200mm-triple-glazed-skylight/

 

 

Now i do not know if this is just Salesmen talk or if it can be done without a problem.

Any Window Installers or Roofers on here?

 

Please enlighten me

 

@pocster someone needs help

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