outside window sill

[John Terefenko]

Anyone replace an outside window sill that is rotted?? What type wood is best for this?? Any special do's and don'ts??

[Aaron Rosenthal]

Yup. I have in my house.
I used Fir, but it's possible in your area southern Yellow Pine might be good.
I made sure I primed all the way around before fitting it.

[Mel Fulks]

Most of the ones around here are fir or hem - fir ( hemlock") . Real fir is much better than hemlock. Many times the sills have been run bark side down. They should be bark side up to avoid the razor blade like grain. The solvent base copper naphthalate will definately add many
years of rot free use. I had a couple sills that had been run the wrong way . I patched them with Bondo and then covered
them with canvas and painted . That is a long term easy fix.

[Bill Dufour]

Redwood is what used to be used in California. My 70 year old ones are in pristine condition touching rotted trim pieces of fir or pine. Of course they are pure heart with no knots which is not sold anymore. The trim I remade in todays redwood and soaked in buckets of the green rot preventer for several days before installing. I used stainless finnish nails to put it all back together.
Bil lD.

[Lee Schierer]

I've used treated lumber to replace rotted parts of windows.

[Jim Morgan]

Depending on the extent of the rot, you might consider patching instead of replacing. Abatron's liquid wood/woodepox combination works well. The first is a low viscosity epoxy that soaks into rotten wood and hardens it up. Then overfill cracks, voids, missing areas with the putty-like woodepox; once that is cured, you can plane/rasp/sand it to shape. Smith's CPES also works well for consolidating punky wood, but it stinks to high heaven.

[Jeff Bartley]

I'll second the recommendation to use the Abatron products, they work really well. One thing I learned from another restoration fellow was that the Wood Epox can and should be applied directly onto the Rot Consolidate (the liquid stuff). In this way the two bond to each other better than if the rot consolidate was left to dry first. And James is not wrong about the smell of the rot consolidate!

If you are faced with replacement of the sill we usually use white oak. Others that would be good include black locust (hard to find), Spanish cedar (on the soft side), or mahogany (expensive).

Believe it or not I really enjoy replacing sills! Even better is when I get to reproduce an old window frame completely.



Depending on the extent of the rot, you might consider patching instead of replacing. Abatron's liquid wood/woodepox combination works well. The first is a low viscosity epoxy that soaks into rotten wood and hardens it up. Then overfill cracks, voids, missing areas with the putty-like woodepox; once that is cured, you can plane/rasp/sand it to shape. Smith's CPES also works well for consolidating punky wood, but it stinks to high heaven.

[Tom M King]

I usually use White Oak, but prefer Live Oak, when I can get it.

I won't use epoxy on South, or West facing walls any more, and especially not in a SW facing inside corner. It breaks down after a decade, or two, from the heat. Inside a SW facing corner, quicker than that. That might be different in places much North of here, but I have had some break down in those places, whereas on the same buildings, the epoxy is fine on North, or East Walls.

[Livingston Johnston]

I'd recommend Accoya. Very rot resistant, very stable, and quite easy to work with.

[Dan Schocke]

I don't mean to hijack the thread, but I'm curious why none of the very experienced folks (way more knowledgeable than me) above mentioned cedar. I don't have much experience with this, but I got really tired of repairing/replacing the painted fir trim boards on my previous house and eventually just ripped it all off and replaced with painted western red cedar. I have since heard something about cedar not working well with white/light colored paint, but that wasn't something that I had any issue with. After the responses that I saw above, I suspect I made a poor choice, though they seem to have lasted.

The fir that I hated was only painted on exposed sides, so I'm sure that was a good portion of the issue -- some of the trim, especially the caps at the top of the windows rotted away to nothing in ~7 years. Sloppy mass-market builder.

--Dan

[lowell holmes]

White oak is a good water resistant wood and has very good strength.

[Mel Fulks]

Dan, way too often hemlock is being sold as "fir". Good fir is good stuff

[Andrew Seemann]

I don't mean to hijack the thread, but I'm curious why none of the very experienced folks (way more knowledgeable than me) above mentioned cedar. I don't have much experience with this, but I got really tired of repairing/replacing the painted fir trim boards on my previous house and eventually just ripped it all off and replaced with painted western red cedar. I have since heard something about cedar not working well with white/light colored paint, but that wasn't something that I had any issue with. After the responses that I saw above, I suspect I made a poor choice, though they seem to have lasted.

The fir that I hated was only painted on exposed sides, so I'm sure that was a good portion of the issue -- some of the trim, especially the caps at the top of the windows rotted away to nothing in ~7 years. Sloppy mass-market builder.

--Dan

I think the bit with cedar is the tannin can bleed through light paint. I'm not keen on it because sometimes it doesn't take and hold paint well, and because I had a nasty case of red cedar asthma 25 years ago. I still start wheezing if I work with it, which I normally avoid.

I prefer white pine for exterior trim. It machines well, is friendly to work with, is stable, takes paint great (with an oil based primer) , and has moderate rot resistance. If it is maintained, it will last indefinitely.

[Jason White]

Cellular PVC like Azek, etc.

[Darcy Warner]

You can buy new sill nosing from Azek.

[Patrick Walsh]

I second what Darcy saiz.

Azek will nosing is the only way to go unless you have some fancy schmancy house with custom mahogany windows or something like that.

[John Terefenko]

They moved my thread so I finally found it and thank all for the replys. I actually have two windows that need repair. One I can do the patching because not so bad. The other needs replacing. I will be painting white again so need wood that will not bleed. They will eventually be covered in aluminum when I do the exterior of the house in a couple years. So for now I need to repair. Fir seems to be the favorite. Will look to see. Ihave not seen thick enough Aztec plastic but that is from Home Depot. All other sills are wood.

[Larry Edgerton]

Versatex is available in 1 1/2" thickness. It is what I use for sills when painted. I recently made some large storms out of Versatex. Storms take a beating as they have warm moist air on the inside and dry cold air on the outside and so do not like to hold on to their paint. I did this as an experiment on my own house, and it is a great success. I ran out of Versatex for the inside stop on a couple so used wood painted. Both of those windows need the bottom stop replaced in two years.

[Steve Demuth]

Anyone replace an outside window sill that is rotted?? What type wood is best for this?? Any special do's and don'ts??

I use the wood of a special tree called the "aluminum tree."

Seriously, I have replaced all my wood outdoor sills over the years with sill constructed from solid, clear pine wrapped in construction powder coated aluminum. With a small sheet metal bender/break the wrapping is very easy, tight and crisp. High quality silicone as an adhesive and sealant on the ends. They'll last a hundred years, easily.

On outbuildings, I have mostly used treated 2X8 lumber for sills. I put those on with a 20 degree rise and a ripped drip edge. They last for decades except on direct South exposures, where the constant sun can be a problem. In future, I'll wrap those in aluminum as well.

[Tom M King]

When I replace sills in the 200 year old houses, I put them in so they can be replaced next time without having to take out any other pieces. Any end grain is saturated with epoxy. With today's better paints, these new ones should last longer than another couple of hundred years.

I have rebuilt some out of cast in place concrete, when they were too close to the ground. After the concrete cured, I covered those with epoxy, getting it to bubble down with a heat gun, and then painted them. Those are holding up really well, so far.

[Eric Anderson]

If you use Azek (and I have used for all the trim on my own house), make sure you get the proper paint. You need a "vinyl safe" paint or else the paint won't hold properly. Sherwin Williams has a vinyl safe line approved by Azek, but you need to ask for it, and I've found that not all of their employees are familiar with it. The vinyl safe can still be used on any other medium, wood, Fiber cement etc.

[lowell holmes]

Check this link.

https://search.yahoo.com/search?fr=mcafee&type=E211US739G0&p=best+wood+species+for+out+doors