I plan to install an integral flanged window into a bevel sided dormer. I’ll have to remove the siding to widen the RO and flash, but what is recommended to shorten the height of the RO ~ three inches. Should I build up the sill or the head.
Discussion Forum
Discussion Forum
Up Next
Video Shorts
Featured Story

The crew talks about work start times, fire-resistant construction, fixer-uppers, building Larsen trusses, and AI for construction.
Featured Video
How to Install Exterior Window TrimRelated Stories
Highlights
"I have learned so much thanks to the searchable articles on the FHB website. I can confidently say that I expect to be a life-long subscriber." - M.K.
Fine Homebuilding Magazine
- Home Group
- Antique Trader
- Arts & Crafts Homes
- Bank Note Reporter
- Cabin Life
- Cuisine at Home
- Fine Gardening
- Fine Woodworking
- Green Building Advisor
- Garden Gate
- Horticulture
- Keep Craft Alive
- Log Home Living
- Military Trader/Vehicles
- Numismatic News
- Numismaster
- Old Cars Weekly
- Old House Journal
- Period Homes
- Popular Woodworking
- Script
- ShopNotes
- Sports Collectors Digest
- Threads
- Timber Home Living
- Traditional Building
- Woodsmith
- World Coin News
- Writer's Digest
Replies
Whatever looks aesthetically better!
I would guess that splitting it and going 1 1/2 each way would keep the window architecturally centered, but you have to look at it so decide what looks best.
When you flash the sill, tilt the sill to the exterior a little to allow water to shed to the exterior once done!
This is what I was thinking. Thanks for the tip.
Mike
Depends on if there are any other features on the house that the window aligns with. If not a factor take your pick. If it were me I'd put 1 2x at the head and 1 @ the sill.
But if you're widening the RO how much more work is it to replace the cripples below the sill with the proper length? Widening the RO will require replacing the header, moving the king & jack studs... why not do the the cripples below the sill?
If I had to obtain more space I see what you mean, it would'nt be that much extra work. I was lucky though, the original window had a 1x on each side. After removing them I had the width RO I needed.
Thanks for the tip,
Mike
It's best to keep the head trim the same on indows inside and out. Any time you can keep it the same it will look better.
Thanks for the tip.
Mike
If the new window's a casement, make sure that if you go up with it, it won't hit the fascia when it's open<G> Someone's got it in for me, they're planting stories in the press
Whoever it is I wish they'd cut it out but when they will I can only guess.
They say I shot a man named Gray and took his wife to Italy,
She inherited a million bucks and when she died it came to me.
I can't help it if I'm lucky.
Thanks for the tip. It is a double hung but I bet if I did install a casement that would happen to me.
Mike
Yeah, I read about it in magazine<G> Someone's got it in for me, they're planting stories in the press
Whoever it is I wish they'd cut it out but when they will I can only guess.
They say I shot a man named Gray and took his wife to Italy,
She inherited a million bucks and when she died it came to me.
I can't help it if I'm lucky.