I mentioned earlier that the back door weatherization needed a bit more tweaking. I finally found the problem.

I’d been put off the scent by the presence of a door sweep screwed to the inside of the inner (wooden) door. It was new, so I figured it was A-OK. Searching for the source of the remaining air leak, I looked at the door edge-on when it was open and discovered that, just like my front door, the back door had a huge gap at the bottom edge. Again, about 3/4″.

So I says to myself, says I, “This will not do.”

For this repair, I bought two thicknesses of red oak lath, 1/4″ and 1/2″ (not sure which I’d need), and another 3-finned vinyl bottom sweep. I couldn’t build up the threshold, as on the front door, because it has one of those aluminum thresholds with a compressible vinyl “speed bump”. It’s in good shape, so removal doesn’t make sense– it’s just not doing its job because it doesn’t meet the bottom of the door. Instead, I decided to build up (or down, as the case may be) the bottom of the door itself, using a hardwood strip.

Filing away damage

First, I took the door off its hinges. The bottom was in poor shape due to water damage, so it needed some work.

The bottom edge of the center board was so weathered that you could flake it off with a fingernail, to maybe 1/4″ in some spots. The outer boards, because they’re vertically oriented and the grain is perpendicular to the threshold, were in much better shape.

I didn’t want to buy a whole new door, but also didn’t want to cut all the way through the bad wood on the center board. The goals were 1) To create a good mating surface to attach the hardwood strip to the door bottom, and 2) Accommodate the slight bowing in the floor surface, which meant the gap was thicker in the middle than at the ends.

Red oak strip in place

I used my router to cut away some of the vertical outer boards so I could attach the red oak strip all the way across the bottom. I used a half-round bastard to file away some of the damaged center wood and generally even the surface. With the new vinyl sweep, the 1/4″ strip was the best fit (I later returned the 1/2″). I had to narrow the strip by about 1/4″ to match the door, and also cut off about that much from the vinyl sweep (same on the front door).

Then I glued-and-screwed the red oak strip into place. Pretty solid, though I really out to get some weather sealant on it.

That pretty much took care of the air leak and I was able to free up the former inside sweep for use elsewhere in the building.

Placing the vinyl sweep

This fix was not expensive and, other than the router, did not require expensive tools. Cost:

Oak strip: $2.84
Vinyl sweep: $10.11
Wood screws: $1.05
Glue (on hand)
Time: Priceless

Tools: router, cordless drill, bastard, handsaw