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In our area you guys are very well thought of. Keep up the good work!

I have a question. The other day I was washing my siding (white vinyl). The outside window sills are also vinyl-clad, but I was able to squirt the water both up the sill, as well as horizontally. The material that came out was some reddish dirt and some fine particles that looked like tobacco and were a golden color. When it was wet, it clumped together. I cannot describe it any better than that. Please tell me it is not chewed wood fiber; the house is only six years old.

Do you know what this is? Will I have to have the vinyl removed and the sills replaced?

Can you help?

Beverly Coyne, Branch Administrator for the Kent Island Office

Dear Beverly,

Okay, I do not believe this is chewed wood at all, judging from your description. I also do not think your sills need to be replaced. I believe what you are seeing are particles of sheathing. Judging from the age of your house, I would suspect your sheathing under your siding is most likely a composite or fiberboard. You probably have seen new construction before the siding is installed, with the framing and sheathing only. Sometimes the sheathing has the appearance of foil, but most commonly it is a dark brownish, more coarse-looking material. The foil-looking sheathing is basically hard foam with foil backing, however the most common and what I believe is on your house is a fiberboard. This material is a composite of wood fibers glued and compressed together. When this material gets cut to fit around windows, doors, sills or any other opening, the tobacco-looking stuff you described is exposed and will fall out where the cut was made. Sometimes you will see reddish dirt looking stuff come out when water gets behind the siding. All this makes me believe all you are seeing are particles from this composite sheathing. This is only a small problem that can be cured with caulk.

To be on the safe side here is what I would recommend:

Have an insect inspection (if you have not in the last year or two)

Caulk around the window where the siding meets the window jam

Caulk around the window where the siding meets the sill

Keeping water from getting under the siding is important

I hope this helps you with your strange stuff!

Hope to hear from you again.

PS— Thank you for the good thoughts