Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > Roofing/Siding

CLICK HERE AND JOIN OUR COMMUNITY TODAY...IT'S FREE!

Reply
 
Thread Tools Search this Thread Display Modes
Old 03-08-2010, 12:46 PM   #1
Member
 
Join Date: Jul 2009
Posts: 72
Rewards Points: 75
Default

skylight questions


I am getting ready to replace my 5-12 shingle roof. It has 2 Velux deck-mount skylights, and I've decided this is a good time to replace them with something newer and more efficient. They haven't leaked, but if I'm shelling out for a 30-year roof, now seems like a good time to replace them.

I was planning on replacing them with new deck-mount units, but local contractors seem to prefer curb-mount skylights, saying that they are easier to seal and offer greater protection against ice, snow, leaks (we live in an area of extreme cold and deep snow).

I haven't been able to find any information on which configuration (deck vs. curb) offers greater efficiency, specifically in terms of winter heat loss. It seems to me that with curbs being built of 2x4 or 2x6, the R-value of the curbs (~1.9) is low enough to offset any efficiency gains in the new fancy argon-filled double pane glass units; heat would be lost through the curbs. Having a skylight sealed directly to the deck should be technically better.

I realize that a skylight is a hole in the roof that will lose heat, but I want the most efficient units that are available.

any thoughts?

longshanks is offline   Reply With Quote
Old 03-08-2010, 09:05 PM   #2
Commercial Roofing
 
AaronB's Avatar
 
Join Date: Jan 2005
Location: Illinois
Posts: 927
Rewards Points: 500
Default

skylight questions


Hmmm

Look for the Insulating values in the manufacturer literature.

__________________
www.roseroofing.net/ Free inspection within 12 miles
Seamless Polyurea Roofing Membranes for Metal Roofing, Roof Leak Repair, Seamless Commercial Spray Foam Insulation, Seamless Commercial Roofing, SPF Roofing, Industrial Insulation, Our trucks are red but our roofing is GREEN!
AaronB is offline   Reply With Quote
Old 03-09-2010, 02:17 AM   #3
Member
 
Join Date: Mar 2008
Posts: 94
Rewards Points: 75
Default

skylight questions


Quote:
Originally Posted by longshanks View Post
I am getting ready to replace my 5-12 shingle roof. It has 2 Velux deck-mount skylights, and I've decided this is a good time to replace them with something newer and more efficient. They haven't leaked, but if I'm shelling out for a 30-year roof, now seems like a good time to replace them.

I was planning on replacing them with new deck-mount units, but local contractors seem to prefer curb-mount skylights, saying that they are easier to seal and offer greater protection against ice, snow, leaks (we live in an area of extreme cold and deep snow).

I haven't been able to find any information on which configuration (deck vs. curb) offers greater efficiency, specifically in terms of winter heat loss. It seems to me that with curbs being built of 2x4 or 2x6, the R-value of the curbs (~1.9) is low enough to offset any efficiency gains in the new fancy argon-filled double pane glass units; heat would be lost through the curbs. Having a skylight sealed directly to the deck should be technically better.

I realize that a skylight is a hole in the roof that will lose heat, but I want the most efficient units that are available.

any thoughts?
You may want to check out the existing V-Lux skylights, they may be argon filled already.
Also putting in a deck mount means removing the drywall in the skylight well. I am sure your contractor doesn't want this mess on his hands.
There is nothing wrong with the deck mount flashing but you are creating an added finishing expense & the deck mount has wood sides as well that are even thinner than a 2x6
Dale Chomechko
DC Roofing Inc
Dale Chomechko is offline   Reply With Quote
Old 03-15-2010, 12:07 PM   #4
Member
 
Join Date: Jul 2009
Posts: 72
Rewards Points: 75
Default

skylight questions


I checked with Velux, and they stated that the deck mount units were considerably more efficient than the curb mount units. They also advised that the new units are somewhere between 20-40% more efficient than what I have. I have had no problems with my existing deck mount skylights, so I bought 2 new ones yesterday. Old ones going to wife's garden shed

The rough opening in my roof doesn't appear to have been sized properly for the existing skylights, and the new units are about an inch narrower than the old ones, so I have decided to re-frame the top of the skylight tunnels and prepare a more weathertight deck/subframe for the new skylights. I am going to remove the old ones and install the new ones, then leave it up to my roofer to flash them, and install felt, ice and water shield, etc. and re-shingle.

2 questions

1) can I use standard door and window silicon to seal the skylight to the deck/subframe, or is there a better product? It will be screwed to the sheathing, but a tight seal is needed.

2) Velux factory flashing or 'custom' flashing made by the roofer? They say theirs is 'bigger and better' than Velux' flashing.

Last edited by longshanks; 03-15-2010 at 12:10 PM.
longshanks is offline   Reply With Quote
Old 03-16-2010, 11:03 PM   #5
Commercial Roofing
 
AaronB's Avatar
 
Join Date: Jan 2005
Location: Illinois
Posts: 927
Rewards Points: 500
Default

skylight questions


I have never needed any type of caulk for a Velux skylight. I have never seen anyone make a better flashing kit than that of the mfg. It is both better and cheaper to go with the Velux flashing. There are no wrapped/cut corners with the Velux flashing, and it is designed for the product.

This is just making no practical roofing nor fiduciary sense.
__________________
www.roseroofing.net/ Free inspection within 12 miles
Seamless Polyurea Roofing Membranes for Metal Roofing, Roof Leak Repair, Seamless Commercial Spray Foam Insulation, Seamless Commercial Roofing, SPF Roofing, Industrial Insulation, Our trucks are red but our roofing is GREEN!
AaronB is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Help How to Wire Bathroom "Fan Heater Light Night-light" unit, and questions Tryvidy Electrical 9 06-18-2012 02:37 PM
How thick should my thinset be? yummy mummy Tiling, ceramics, marble 20 09-28-2009 12:36 PM
Skylight on a flat roof? mchardo Roofing/Siding 6 02-19-2009 09:12 AM
Flat roof related questions christy123 Roofing/Siding 8 12-09-2008 11:30 PM
Laminate wood floor layout questions nathan.tran Flooring 4 08-30-2008 10:56 PM




Top of Page | View New Posts

Copyright © 2003-2014 Escalate Media. All Rights Reserved.