You'll Pay A Price For Hidden Downspouts' Good Looks

Q: We're talking with the architect about downspouts on the house we're designing. My fiance wants hidden downspouts. The architect was not especially keen on the idea and said that often they get blocked and they will drain inside the house. My fiance was skeptical, saying he hadn't heard of that. The hidden spouts are supposedly very pricey and a little harder to do. What would be your advice?

A: Hidden downspouts are a design feature seen on the very most expensive customized homes in our area. Conventional downspouts are mounted to the outside of the building and are attached to externally mounted gutters.

On flat roofs, and on pitched roofs with integral gutters (not externally mounted), it is possible to have downspouts completely hidden from view. This makes for a cleaner look to the building, highlighting certain architectural details without the visual distraction of downspout pipes.

To eliminate leakage inside, the pipes themselves they are typically 3- or 4-inch round ABS plastic drain pipes with glued fittings. This is the same material and method used for sewage disposal. They shouldn't leak inside the walls, especially if they are water tested as are all plumbing waste lines.

The junction with the roofing material is the weak link in the chain. If the scupper is not sealed perfectly to the downspout, it can very easily and quickly create a leaking problem.

The architect will need to give very specific instructions if this is to work correctly for many years. Also, make sure there are gravity overflows, so if (when) the system plugs up, water will have a way out other than running down into the soffit or walls.

I would dissuade you from hidden downspouts if the home is in an area with a large number of trees, as this would make clogging even more likely. Try to provide a cleanout or openable hatch somewhere in the system to clear clogs and also a downstream fail-safe overflow.

The noise of water running and dripping inside the walls may be a bit disconcerting; consider using cast iron pipes (raising the cost, obviously). If you still cannot be dissuaded from hidden downspouts, but are hesitant about having running water inside the walls, there is another option: Put the pipes outside the shell of the building and build a false box to conceal them. Done right, these protuberances may not even be noticeable. And finally, if your fiance just doesn't like the look of aluminum downspouts, take a look at some of the great looking gutters and downspouts available in alternate materials, such as copper or stainless steel.

Q: I have some foundation leakage with all the rain we've had lately. It has happened occasionally in the past during extremely heavy rains. The water seems to be coming from between the cement floor and wall. I don't know who to call or what to do to stop this situation. I certainly don't want to spend $5,000 fixing this. Can you help me?

A: This problem can be very complex, and there are usually no simple, complete solutions. That said, there are a few basic and easy first steps you can take to minimize the damage and risk of future occurrences.

Look at the downspout drains and where they go. Do they get water away from the house adequately? If not, provide splashblocks to carry the water at least several feet away. If the water goes into a subterranean pipe, could this leak right into your foundation? To test, run a hose down the line for a half hour or so when it's not raining. Many of these lines are compromised in some manner and deliver water right to the point of leakage. Does the yard slope away from the house adequately? If not, make it so. If for some reason this is not possible, make provisions for a swale or dip to carry water away laterally.

There are many hydraulic patching cements available at reasonable prices. Apply according to directions to leaking interior concrete wall areas. These patches will actually stop active leaks. Be aware that sometimes this may create a leak in another area because the hydrostatic pressure must be relieved somehow. But for the money, it certainly is worth a try.

If you want professional help, contact as many people as you can. Rather like religion, engineers, general contractors and waterproofing outfits all feel they have the answers and everyone else is wrong.

Ask The Expert answers readers' questions every Saturday. Send questions to Ask The Expert, Seattle Times, P.O. Box 70, Seattle, WA 98111, or call 206-464-8514 to leave your questions on Ask The Expert's recorded line. E-mail address is dhay@seattletimes.com

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