Hi,
I’m restoring old windows bays and I’m considering replacing the sills which are worn and curving upwards, not clearing the rainwater well.
Should I chisel out the old sill and replace it with an entirely new piece that slopes downward, away from the window to clear the water?
Also, any recommendations on which type of wood to use? Something that will last long in the North East?
Here’s a downward shot of the sill.
Many thanks in advance.
-ww
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Replies
White Oak was the wood sill choice here.........
in NW, Ohio in most masonry areas.
I use a Multimaster from Fein to surgically cut out wood.
Refastening like the original will probably not be possible so you'll have to use your noggin to come up with something that'll work in your application. Jamb removal would be best-but not usually possible.
I'd consider epoxy if the sills are not badly rotted. Something like West Systems.
Are you replacing the entire sill or just the chewed-up part? The outer sill appears to be in primo condition.
Maybe the entire sill. It's pretty old, 1880.
Sills are normally nailed up from the bottom into both jambs. Reattaching a new jamb may be problematic without removal of the entire window unit.
I recently replaced a sill that was in real bad shape. Although I was not able to nail up into the jambs, it was a nice tight fit and I used adhesive and nails in other locations.I'm happy with the results.
Build it right with a slope to shed water and dry pine is fine. I primed all sides of the sill before I installed it.
Caution: If you remove the sill you may find that the jamb bottoms are damaged making a tight fit with a new sill difficult.
If I were you I might first try sanding down the sill including the upward curve and then try wood hardener and epoxy to fill the checks. You just want water to run off. You should place the epoxy only down into the checks and not on the top surface. If you cover the top surface with epoxy, you will trap moisture in the wood resulting in rot. Sand off any epoxy on the surface before you paint.
Rick
I'm looking at the photo again and I'm not sure that I see any deep checks in the wood. Maybe you just need some sanding and paint on that sill? Is the sill loose and moving around or is it secure to the jambs?
Thanks for the reply. I pulled out the sill yesterday and saw that most of it has tons of dry rot. Only the top was painted. It was nailed from the bottom up into the jamb. I think I may cut out the bottom of the window bay to reinstall the sill, and nail/screw upwards into the jamb, hopefully, for a tight fit. It was rather surpising to see how the space between the bay wall and stone front had no insulation. Perhaps will fill with pink spray foam then put in the sill.
The photo looks alot like the window sill I replaced. Mine was a brick/block house.
I cut a rabbit on both ends of the sill with a router. I then slid the new sill into place after putting something like PL premium on the area that meets the bottom of the jambs.
So the sill was placed on stone, and then sometime after that the stone was stuccoed/mortared up flush with the sill? That mortar kept the sill from draining properly and contributed to the rot. You need to reconsider the layout there so the bottom of the sill is above the masonry.
Unrelated: If the jambs are sound enough I'd consider using a pocket screw jig to attach the new sill.
I'm not sure how it was constructed. Honestly, it may not have been replaced since 1880. The bottom of the sill is natural, no sealant or paint, so it was pretty much shot. Someone actually drilled the sill into one of the facade stones to hold it in place. I think we may PL the sill to the jamb and screw as well. Keep it away from the stones as well.
-ww