Sag in roof could mean trouble

Q. We have a Cape Code house with a full shed dormer on the back which was added later on. Now we've noticed a significant depression in the front roof which dips into the ridge pole. What is the cause and is it serious? What can be done about it?

* Also, what happens in a bathroom if the moisture-exposed wood is stained but not varnished? Ann Hattes Danvers, Mass.

A. It sounds to me as if someone may have made a major mistake in the reconstruction, either in poor workmanship or, more likely, in inadequate engineering and design.

I would urge that you immediately get in touch with a licensed engineer or architect and ask him to inspect the deflections, state the cause, and tell you how to have it repaired. Don't delay a day in making corrections for the safety of the occupants as well as the structure.

In other words, the structural deflections may be serious.

Construction is science as well as art. It is based on known mathematical rules and structural laws. To disregard or guess at them can trigger grievous consequences.

There is no room in design and construction for Mickey Mouse guesswork whether in new building or remodeling.

* As for the stained woodwork in the bathroom, unfinished lumber can roughen or deteriorate eventually from the effects of moisture. Indeed, the moisture should be isolated from raw woodwork by varnish or some other washable finish.