Sunday, September 30, 2007


I like our house, it's got a number of fun, interesting features.

However, the guy (gal) who designed it showed remarkable lack of design skills in a couple of areas. Today (because it is raining), I feel like ranting about the roof and the gutter (drainage) system.

First, the roof lines are fun and visually interesting from the street. Whee.

However, on one side of the porch, the major beam that runs across the porch juts out past the roof line. What does this mean? Horizontal wood (painted) is exposed to rain. Not only that, but an entire roof drains onto this piece of wood. They (as an afterthought) added a piece of flashing over the top, but only made the flashing extend to cover two-thirds of the exposed wood. Eh? The 15 cents of aluminum saved was not worth it. I repainted the wood with several coats this summer, but failed to put up a bigger piece of flashing (it will go up before the winter has really begun).

The downspouts all around the house are "aimed" at the pipes that drain to the sewer. yes, they "aim" in the general direction, but they don't really drain directly into the pipes. Most are rectangular downspouts that end 1/4 inch above the beginning of the circular drainage pipes. And, no, they don't line up exactly. A couple of the downspouts are crimped at the bottom to "ensure" the water all goes into the pipe. While that makes sure more of the water gets in the pipe, it creates a wonderful blockage for any debris that falls down the downspout.

The best feature is a drainage area behind the garage. See, the two north/south peaks in the front of the house drain to a flat area above the front porch, which is serviced by two downspouts. The one in front of the garage seems to be OK, as it's surrounded by a sea of aluminum flashing with no seams (thank god). So debris in that area has plenty of space to collect and not cause any major problems. However, the one behind the garage is just a mess. First, it all collects to a single channel that runs east/west, continuing to collect rain from a third peak above the master bedroom. So an inordinate amount of rain collects in this tiny location. The flashing is pretty high along the vertical surface, so all is not bad. However, it drains to one point where it dumps into a square section of gutter, perhaps 4 inches square.

Yes, about one-tenth of the roof drains into a 4"x4" section of gutter. That's roughly 4000 gallons of water draining into 16 square inches of space. (1/10 * 1600 square feet * 40" of rain per year)

Of course a couple of leaves and a few pine needles are all that's needed to clog up that little space. Why? Well, if water builds up just before it reaches the gutter, water will flow along the south-facing exterior wall and drain down the wall, flowing over the garage window, and continuing down to the ground.

Oh, but it gets better. Presume, for a second, that there aren't any blockages at the gutter. The downspout immediately bends 45 degrees, flows 5 feet, and then makes a 90 degree bend into a jury-rigged connection with another downspout. Yes, they crimped the end of the 90 degree bend and shoved it into a hole in the other downspout, and liberally applied caulk. This little junction commonly fills up with gunk (usually sediment from the shingles) and the rain backs up to the 45 degree bend where it pours out, and, you guessed it, down the side of the house, over the window, and to the ground.

I have added wire mesh to all of the downspout/gutter connections, so this helps prevent debris from entering (clogging) the downspouts, and it also allows water to drain longer. But the fundamental design of the area behind the garage just blows. The water pouring over the window is certainly what has caused water damage inside the window (in the garage), and I'm sure the design has let water come into the garage and cause the mildew bloom we had in the garage.

Hopefully the occasional cleaning of the gutter and the wire mesh will keep us from having any problems. But I'm pretty sure I'm going to redo the downspout in that corner and just have it drain under ground into a French drain. I'm still not sure how I'll manage ensuring all 4000 gallons get into the downspout, but something will come up.

It just means that when it rains every fall I watch the water pour over the window and get to go out in the wet to clean the gutter.

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