| Many of the wooden horizonal window sills (the horiz. piece at the very
| bottom) have rotted badly, and needs replacement, or...
| How is this usually handled:
| e.g., is the old sill just cut back the few inches of its width, and a
| new piece screwed or nailed in ? If so, is this a good approach ?
| Or, should the whole window be replaced ?
Most of the older sills are made of very hardy wood. I'd
guess fir. Those rarely rot and when they do can usually
Unfortunately, most newer windows (35 years is new in
this case) are made of plain pine, often with glued-up
sills that begin to break up after years of water exposure.
Making matters worse, most paint used in the past few
years has been water-base, which simply doesn't hold
up on horizontal surfaces.
Typically, to replace a sill, you need to take off the trim
in and out, then deal with the window itself. If you have
something like a 1980 Anderson window it might be tricky
to replace the sill, but it can be done. I'd use fir if it were
me, so you don't end up doing the same job again in 10
The replacement is a lot of work, so I try to use a stopgap
measure when it's feasible. There are 3 basic options:
1) Gouge out the rot and fill it with bondo. Prime with
good oil primer and paint.
2) If it's bad and you don't care much about looks, you
can repair as much as possible and seal the wood, then
cover it with aluminum or vinyl.
3) If it's really shot but the damage doesn't go in too
far, you can trim it off and glue on a new piece. (Again,
I'd use fir and use Bondo if necessary to fill the joint
before priming with oil paint.)
| If replaced with a "storm window," like the ones Andersen sells, do
| these have a built in sill, or would the sill still have
| to be replaced ?
You can replace the whole window. I don't know
what you mean by storm window. To me that means
an aluminum frame with two panes and a screen that
gets screwed to the exterior casing. But if you mean
to use a new window it will have its own sill. The trouble
there is that you'll need to remove and redo both the
inside and outside trim.