Q: One year ago we had some repairs done to an outside chimney. Since red mortar was used when the house was originally built, our repairman colored the new mortar with jeweler's rouge so it would match. After he was done we noticed red splashings on the house (white siding) after every rain. The chimney repairman then sprayed the repaired area with silicone, but the red keeps leaking out after every rain. Can you help us?

A: To color mortar or cement limeproof and wateproof dry color must be used. I never heard of anyone using jewler's rouge for this, but I imagine it is simply leaching out with each rain because it is water soluble and does not mix with the cement. It is also possible that the repairman did not mix the red coloring with all the mortar - he may have added thered powder to the surface. I think the only cure now is to rake out the joints to a depth of at least 1/2-inch, then replace with properly mixed new mortar - only this time make sure the mason colors it with limeproof dry color sold for use in cement and mortar. Don't be surprised, however, if the color doesn't match Perfectly.

Q: This winter left my concrete driveway in bad shape. Sand and gravel are exposed in many places, and there are a number of cracks. Some sections actually rose up, though they are now down to normal level. What can be used to cover the shallow holes and fill the cracks?

A: The shallow depressions and small cracks can be filled with vinyl concrete patching cement troweled on in layers as thin as one-sixteenth of an inch, that will bond in shallow depressions and cracks without the need to undercut. The sections that buckled did so because the ground froze and heaved, causing movement of the subsoil. This may mean a lack of proper foundation under the driveway, and it is possible that the whole thing will happen again next winter.

Q: Last fall I applied stain to my new front door, but before I could apply the varnish cold weather set in. To prevent warping it was suggested that linseed oil be rubbed on, so I did. Now I see that the directions on the varnish say that it should not be used over dirt, wax, oil, etc. I still want to use varnish now that the weather is warmer. What do you suggest?

A: Since I don't know whether you used boiled or raw oil, or how heavily you applied it, I can't say for sure if there is enough undried residue to cause a problem. I recommend, therefore, scrubbing the surface with paint thinner and fine steel wool, just in case any, residue of undried linseed oil remains on the surface. Dip the steel wool into the thinner and rub lightly, then wipe immediately with a lintfree cloth. When this dries you can varnish.

Q: The concrete wall in the basement of my semi-attached house has three thin cracks running from the top of the basement ceiling to the ground. They can be seen from the outside as well as from the inside. Do you know what is the cause, and what can be done about them?

A: As to the cause, it is impossible to say for sure. It could be a poor mixture of concrete, or it could be settling of the foundation and/or footing on which the basement rests. I suggest having an experienced mason contractor look the situation over. As for patching the cracks, you can do this with either hydraulic patching cement or vinyl concrete patching cement. Since hydraulic cements expand as they set, they may be longer lasting in a crack such as you describe if it is due to settling or shrinkage.

Q: I can feel cold air coming into my basement through a space between the top of the concrete foundation and the 2x4 sill that serves as the base of the house wall. The floor seems to rest on top of these 2x4's, and the wall is built on top of the floor. I cannot extend the insulation down from the walls easily, but want to know how I can seal off or insulate this opening.

A: Depending on the size of the openings or cracks, you can seal the open spaces on top of the concrete with either caulking compound or patching where possible, wherever there is at least a half-inch gap. Then I would use caulking compound from the outside on smaller openings, as well as over spots where cement was applied from the inside.