Hi all, how do I go about replacing a rotted window sill? It has rotted on the outside of the window and the rot goes about a half inch in to the interior (past the aluminum storm window). Can I replace the sill without removing the entire window?
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I'm not sure how old your home is, and what kind of window you have. It sometimes makes a difference.
This might be a case where you want to try the epoxy systems; dig out the rot, put in the stabalizer and then fill it with the fillers, smooth and prime. Try a boat repair place, or a good fibreglass place.
Quality repairs for your home.
Aaron the Handyman
Vancouver, Canada
In line with what Aaron said, check out http://www.shopabatron.com/Merchant2/merchant.mv?Screen=CTGY&Store_Code=Abatron&Category_Code=1009000 They make a product called WOODEPOX specifically for this application.
Another option would be to remove the aluminum window, cut back the wood sill with a 3½ or 5" circular saw then chisel out the ends of the cut, and then biscuit-join a replacement piece of stock to what's left of the original sill. Use exterior-grade glue, and place a biscuit every 12 inches or so.
Dinosaur
'Y-a-tu de la justice dans ce maudit monde?
I do about 20 of these a year
1. open the window and cleanup as much as you can.
2.If there is too much rot to rebuild with epoxy you will have to cut the sill out.
3.Use the inner sill edge as a guide for your saw to cut a straight line as far as you can.
4. Next draw a straight line to both jams and then drill holes right next to each other following the line.
5.Now drive your chisel into the holes until the piece breaks free then cleanup your edge with the chisel.
6.Now take a piece of treated 2x6 and cut to lenghth from outside edge of brick mould to br. mould.
7.Cut a 15 degree angle to match the cut in the sill you will have to remove stock on each end to fit under the jams and I usually cut the brick mould at a 15 degree angle so that it is the same clearance as the jam.
8.you will have to plane down the treated 2x6 until it matches up to the sill pieces thickness.
9.Shims will be needed to force the new piece to line up with the existing sill.
10.Once you have made the piece the right size and shape caulk heavily under each jam and then drive your piece into position.
11. I use 4-5 inch scews to pull the new piece up tight to the old piece predrill new piece and counter sink holes.
12.you will have some slight gaps so fill these with caulk or epoxy and wipe flush.
13. Caulk at the meeting point of the jams and sill so that no water can get back in at these points.
14.Prime with oil based Kilz and then paint a couple hours later.
15.Check all other sills to see if caulk has failed and redo caulking.
ANDYSZ2I MAY DISAGREE WITH WHAT YOUR SAYING BUT I WILL DEFEND TO THE DEATH YOUR RIGHT TO SAY IT.
Remodeler/Punchout
Actually, if you've got good hands and are really careful, you can make the cut with a recip as a 'plunge' on a very shallow angle. You won't have more than a stroke length left to chisel out that way; not that much if you've got big brass ones, LOL.... But I wouldn't suggest that to anybody who doesn't use one of these things all the time.
That done, whether to biscuit, dowel, or screw is half-a-dozen of one, six of the other....Dinosaur
'Y-a-tu de la justice dans ce maudit monde?
I like the screw method because it allows me to adjust if needed or redo.
ANDYSZ2I MAY DISAGREE WITH WHAT YOUR SAYING BUT I WILL DEFEND TO THE DEATH YOUR RIGHT TO SAY IT.
Remodeler/Punchout
Good enough reason, I suppose. But if you glue or epoxy it, that adjustability kinda goes away, I would think, LOL...
I'm outta here--gotta go pick up a floor sander and start making dust at the site. 3 month basement reno on the home stretch and the HO is due to come look-see around Memorial Day....
Ciao fer NiaoDinosaur
'Y-a-tu de la justice dans ce maudit monde?
I'm in the middle of a couple of sill replacements now. I am sold on the closed-cell polystyrene (a.k.a. plastic composite) sills and sill nose for replacement. They will never rot, cut and shape like wood, won't split, are dimensionally stable, and seem to hold paint well. My only problem is how best to attach the sill. The original sills are attached to the rest of the window unit via rabbit grooves in the jambs, and nails/staples. Once the old sill is out, the rabbit grooves are often too hashed to be useful, and even if they are intact, nailing isn't an option due to limited access. Once the sill is shimmed flush with the bottom of the jambs, what is the best way to secure the sill? The easiest way is to screw through the top of the sill into the underlying framing, and then thoroughly caulk the countersunk holes. But I hate the idea of penetrating the sill with a hole of any kind. The only other approach I can think of is to use construction adhesive to bond the underside of the sill to the solid shims. Yet, that doesn't fill me with confidence, either. Thoughts..?
The cut and shape like wood part is questionable.I don't think you can plane or trim the outer parts to fit under the jams very easily and ripping it to the appropriate depth can be difficult because the saw blade gets hot and starts melting the plastic.
Are you going to remove the whole sill interior to exterior or cut back the sill to good wood?
I like to attach my made piece by drilling thru the front and running 4' screws thru the front.
ANDYSZ2
I MAY DISAGREE WITH WHAT YOUR SAYING BUT I WILL DEFEND TO THE DEATH YOUR RIGHT TO SAY IT.
Remodeler/Punchout
I've tried the cut and patch/wood epoxy approach on a couple of windows. Won't really know how effective that is for a few of years, though.
On my current window, I removed the entire sill. The replacement sill and sill nose (2-pieces) are the proper depth so they only need to be cross-cut to length. Haven't experienced any heat build-up problems on the table saw with those short cuts, although the aroma of fresh-cut plastic leaves something to be desired. Anyway, screwing through the front edge wouldn't work for me (unless I went through both the nose and the sill at an angle with an impossibly long screw to get down to the framing member. Hah!).
I'm the last guy on this board you ought to ask for advice about working with plastic replacements for wood, LOL. But since you already did, well, Screw It!
Yeah, just screw it down, and plug the holes by melting some P-tex candle into it. P-tex does a pretty amazing job of filling and waterproofing holes in a ski base so the wood core won't rot; it ought to have no trouble handling occasional water on something static like a window sill. It's available in colours, too, if you want to try to match the colour of the plastic sill you're using. Melt a good sized blob into the screw hole, let it overflow a bit, blow the flames out if they don't go out by themselves, and then when it's cooled off, shave it off flush to the sill surface with a cheese-grater 'plane'. Fine tuning is done with a cabinet (or ski) scraper.
Don't let this wonder product lull you into ignoring good flashing under that sill, though. That's basic to any window installation or refit.Dinosaur
'Y-a-tu de la justice dans ce maudit monde?
Rotted sills are a pain to fix- and why are they always on the 2nd floor? We pull the triple track storm frame then install a 3/4 piece of plywood (about 8-10" wide) flush with the casings with angled trim head screws. Here be the trick- We use a Crane flush cut circular saw to zip off the rotted sill using the plywood as a fence. A little trim with a sharp chisel on the ends, some mahogany glued and screwed on and fill the holes with 3/8 mahogany plugs. Don't forget the drip groove on the underside of the new sill. We do a lot of these repairs and once you get a system going it moves right along.
What and where does the drip groove go?
saw kerk down the bottom lenght of the sill, about an 1/8-1/4 back off the front edge, about an 1/8 or so deep.
It keeps the water from wicking back up the underside of the sill nose