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JohnM524
Casement window sill replacement

I've seen a step by step TOH procedure for window sill replacement, and I've also seen Tommy's video. My question is about casement windows. I have some West facing Anderson style casements that see a lot of weather. The sills and the brick mold have begun to rot. Is there anything unique about casement sills, or can I simply replace them as shown by Tommy's video for a double hung window?

Part 2 of this question, do vinyl sills exist for casement style windows? The vinyl sills that I find at the hardware store are about twice the thickness of my casement window sills.

dj1
Re: Casement window sill replacement

1. I haven't seen the video, but there is no question that the sill can be replaced.

2. Your local hardware stores carry limited supplies because of the shortage of space or the high cost of keeping inventory. A Google search will probably help you find the thickness you need.

Mastercarpentry
Re: Casement window sill replacement

Perhaps you also saw Tommy doing an epoxy repair on a rotted sill- if not that may be a good solution for you if the rot isn't extensive. I've had good success with that where all of the riot was accessible from the outside and there was still enough wood to offer proper structural support. The wood epoxy bonds well and also expands and contracts at a similar rate so long as the wood doesn't get wet anymore afterward.

Phil

JohnM524
Re: Casement window sill replacement

I'm sorry to take so long to get back. I did successfully remove the rotted exterior trim (brick mold) using the oscillating saw shown in Tommy's video (now accessible with a search for How to 'Replace a Rotted Windowsill'). This cuts through the very heavy nails that hold the trim on, and also help to hold the window in place. Prying the brick mold off is not feasible since these are very long, heavy duty galvanized nails. If you tried prying, damage to the window would result, or you might even push the window assembly into the house. I replaced this brick mold with plastic (PVC). I also used the same oscillating saw, using a half-moon sawing blade to remove the rotted sill nose. The PVC nose that I purchased locally would not fit perfectly without a little adjustment from my router (mounted on its table). Most of my effort was complicated by an exterior stairs that leads from our deck to the ground. This was solved using an articulated ladder on which I mounted a semi-permanent wood platform.

In my research I was not able to find anyone attempting to replace or repair a sill for an Anderson style casement window, so I was a little apprehensive. My work was also complicated by never being able to find a nice full day where I could tackle this project. As a result I worked slowly and methodically, and hour or two at a time. I also used stainless steel screws for fastening everything. This let me to temporarily assemble and disassemble the project several times to accommodate my shortness of time (the window had to be secure every night). Frequent setups moved me to list the necessary tools, and to find location convenient places to hide them.

I have four more of these windows to repair. The first one took me 30 hours. I expect the next one will take me 6-8 hours. I hope to get this down to 4-5 hours by the time I do the last window.

Thank you Phil and dj1 for your help and encouragement.

John

Mastercarpentry
Re: Casement window sill replacement

And Thank You John for dropping back in and letting us know how it's going. Folks like you really make our day :cool:

Phil

Sombreuil_mongrel
Re: Casement window sill replacement

I replaced a bunch of casement (and double-hung) sills 2 summers ago for a customer; The house was built in 2001. We pulled the units and treated the window jambs as needed with penetrating epoxy (ART prime-a-trate an gel epoxy filler) and replaced the sills with spanish cedar I milled on-site to match. Other than the inconvenience and cutting out of the stucco, it was a piece-o-cake.
Casey

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