Bostonia: The Alumni Magazine of Boston University

Ask the Expert: Kevin O’Connor
Readers took advantage of our invitation to ask Kevin O’Connor about home-remodeling. Here are some of those questions, along with O’Connor’s responses.

QWe are adding a master suite and bedroom atop a 1967 ranch in Darien, Conn. We need to raise the chimney. We may have room to keep the existing concrete encasing (in the attic, about to become new bedroom wall) around the two fireplace and one oil burner flues. Is it safer to keep old concrete surroundings and just extend the chimney up past new roof line, or are the new flues with more flexible modern insulation requirements safer to be built, starting on the floor of the new second floor? What would be some important pointers regarding insulating?

Also, we are extending the sink and dishwasher area out three feet, cantilevering with a post into our deck area. Will the eight-foot space under that three-foot extension cause insulation headaches, or would it be better to fill in the three-foot extension space under the deck with an unheated tool shed or something against brick wall of walkout basement? If we skip the shed, what type of insulation would prevent sink/dishwasher/pipe problems?

I wish you could bid on the project. We’re excited! — Adria Bates

AI have to pass on the chimney question as it’s out of my expertise, and in any regard, it would be best to have a mason look at this specific situation. This is not a question that is served well by a general answer. You don’t want a chimney fire or to mess around with flue gases.

With regard to the extension of your kitchen, I can say it’s always best to keep the plumbing inside the conditioned space. If you can add walls to the three sides of the extension, that would help, even if the space underneath is not conditioned.

But regardless of what you do with the walls, treat the space as if it were completely outside and insulate it well. Local code should dictate the minimum r-value of insulation needed in this situation, so check with your plumber or builder. In this case, expanding foam insulation is preferable to fiberglass because in addition to its r-value, the foam will cut down on air infiltration and make a better seal against the cold. Closed cell foam insulation will have a far superior r-value per inch than both open cell and fiberglass insulation, so I recommend paying a little extra money for the peace of mind.

And if the extension is going to be finished on the underside, consider building in an access hatch in case you need to get to the pipes at a later date.

QI live in a single-family home built by my parents in 1955. I have a problem with banging pipes when the heat comes on, present since the home was built. The banging lasts for about 45 seconds or so—not long but very loud, as if someone were hitting the pipes with a hammer.

This is a hot water, oil burner heating system with cast iron baseboard heating “units” that extend along the full length of three walls in most rooms. The kitchen and the foyer each have what might be considered a "standard" 40-inch-wide-by-20-inch-tall cast iron radiator, rather than that baseboard heating. Those baseboard "units" in most of the rooms are about six inches high. Bleeding of the pipes doesn’t help eliminate the banging.

The room with the most banging is my bedroom, which is above an unheated garage. There is access to the heating copper pipes for most of the rooms in the house in the ceiling of the basement below them. But because the ceiling of the garage is what I think is cement, with some fluffy insulation above, there is no access to that piping from below for my bedroom, or for an adjacent bedroom also over the garage.

Have you a solution for me?— Gerald Strassberger

AOur plumbing expert, Richard Trethewey, has tackled this problem plenty of times, and from working beside him, here’s what I think is going on: There are a couple of reasons your pipes might make noise. The first is something called “water hammer,” which is when a valve closes quickly and the weight of flowing water slams into the closed valve. I don’t think this is your issue, however. Instead, I think your copper pipes are expanding and contracting as they go from cold to hot. Copper expands when it heats up, so when you turn on your heat and the hot water starts flowing through them, the pipes get longer. And those pipes are held to the floor or ceiling joists with fasteners, causing friction when they expand. Hence the noise.

Wherever possible, try to relieve that friction, at either the fastener or wherever the pipe comes into contact with the home’s framing, walls, or floor. Wrap a piece of rubber or cardboard around the pipe so it can more easily move as it expands. A good picture of what I’m talking about can be found here:

http://www.thisoldhouse.com/toh/skill-builder/0,,460783,00.html

I hope this helps. Cross your fingers that expansion and friction are only occurring in those places that are accessible.

QWhat is the best (least disruptive) and most cost-effective way to remodel a basement or room with plaster walls? The plaster is constantly falling when improvements are done in the space, and it is time to get rid of it completely so the basement can be better weatherproofed and updated. (I am a huge fan of the This Old House series.)

I sincerely thank you for any information you can offer. — Adrienne Vyfhuis

ABefore you undertake any basement remodel, determine if the space is wet. If it takes on water, consider leaving it unfinished, or make sure you seal it up and allow for proper drainage. This can be done with an interior perimeter drain, a sump pump, hydraulic cement to seal cracks and gaps, a good sealing paint such as Drylok, as well as work on the exterior to keep the water away from the house. On the outside gutters with good downspouts that direct the rain away from the house, a French drain and proper grading are your best friends.

If the space isn’t perfectly dry but dry enough to refinish, consider using materials that will prevent mold, such as paperless wallboard, pressure-treated wood or metal studs, synthetic fibers for the carpet, or, better yet, no carpet at all but ceramic tiles instead. I recently put carpet in my basement, but made sure to use carpet tiles instead of wall-to-wall carpet in case I needed to remove or replace some (which I did!). It’s a lot easy to take up a few carpet tiles than to patch or replace a room of wall-to-wall carpet.

New drywall should hold up much better than your old plaster, but you might consider a bead board or wood panel look, too. You can by 4'x8' sheets in many different styles and materials and apply them to the wall.

Lastly, consider hiring a company that specializes in basement remodels. They generally are more experienced with these spaces, and that means they can assess how wet the basement is and then tailor the remodel to address your conditions.

QWe built a home in 2004 and have a metal door that opens to an upper deck. Every time there is a wind/rainstorm, water somehow gets under the door, and it is getting onto the floor and into the underneath wall. We have tried many things to fix the problem, but still water. We had someone come and look at it, and he put an edging strip at the bottom of the door and extra weather facing on the step under the door. Sealant and weather stripping and other things are not working. I am worried about water damage to the walls underneath. Do you have any suggestions? — Joyce

AA good seal at the bottom of that door is critical, so make sure the work that was done in that spot was thorough. Also, keep in mind that even though the water is ending up at the bottom of the door, it could be getting in elsewhere. A door is a penetration into the wall and has to be properly flashed around ALL its sides. The water might, for example, come through the upper corner and then run down behind the casing or even inside the wall cavity. See if there are any signs of water damage anywhere else around the door and even consider taking off the exterior casing for better access.

If the problem persists, you might have to remove the door and re-flash around all four sides before reinstalling the door.

Norm Abram, our master carpenter, dealt with a similar problem and dished out some good advice of his own. Check it out here:

http://www.thisoldhouse.com/toh/asktoh/question/0,,349999,00.html