A Buyers/Owners Guide to Leak Problems at Splines & Gaskets on Log Buildings
InspectAPedia^®  -    

• How to find and fix air or water leaks in log house walls: missing gaskets, splines, caulk, sealants
• Log T-jamb, caulk, spline, gasket, and coating product guide for log houses - where the leaks occur
• Guide to Diagnosing & Repairing Leaks & Other Problems on Modern Kit Log Homes
• Window & Door Installation Details for Log Homes can prevent later leaks & Damage

In this photo of a log home kit wall being assembled you can see the ends of between-log gaskets protruding out between every log course - or can you? Count down from the fifth log from the top and the sixth log from the top of this wall at the right hand end - was this log gasket forgotten? (Maybe not, it may have been trimmed "short" - we can't see for sure in this photo.)

In the speed and excitement of constructing a modern milled-log home, we can testify from first-hand experience that it's embarrassingly easy to make a mistake or two. Working in the assembly of a beautiful manufactured-log home years ago we split into teams. Paul Galow and we did the layout on the newly-constructed first floor deck, making sure that our measurements were exact - because the logs were cut to within 1/16" of spec themselves.

A second log house construction crew, the log set gang, began carrying logs up from the log stack onto the first floor decking, placing each log in numbered sequence according to the manufacturer's plans and instructions. (Yes we read the instructions, and no, this photo is of a different log home construction project that did not go as well as ours.)

A third log construction crew had the job of placing gaskets and caulk as the specs called for on top of each log course before the next course of logs was placed.

We followed the log-set gang with our log drill and log spikes to secure each new log course in place.

The log placement crew excitedly set each new log in place - but on a few occasions they were ahead of the caulk, and gasket crew. Some logs were placed without the proper sealant between log courses - something that was virtually impossible to correct after more courses had been set and spiked in place. Later it was up to us to find and fix these construction snafus. The new log home owner, Jeff B. (my daughter Michelle's soccer coach) was working like mad carrying logs, but Jeff didn't bargain for leaks and drafts in his new home.

In our second photo (above right) the retrofit of caulk at the outside of the log home corners told us that someone had been trying to stop a draft.

Probing behind the caulk (photo above right), or where there was no caulk showing at other corners (above left), if your probe reaches into the mating log faces for a distance greater than the overlapping intersecting log without finding any obstruction, the corner was not sealed with a gasket or caulk during construction. (Use a ruler longer than our little 6" unit here if you don't want to lose it inside the log wall.)

Inside this home near one of the intersecting log corners we can observe several leak stains over the collection of Marilyn Monroe souvenirs. Monroe died in 1962. Given the leaks and drafts in this corner, if Ms. Monroe were alive and visiting this particular home in winter, the leaks and drafts would surely have discouraged the striking of a suggestive pose.

Splines, gaskets, or caulk are also specified between the ends of abutting logs. As you can see from our ruler in this photo, there was no obstruction between the indoor and outside surface of these butting logs in this leaky log home.

Without a doubt the butt joint of these two logs was not splined nor sealed against water leaks and air drafts. The stains on the log ends confirm that water has indeed leaked into the structure at this point.

Having worked on a log home construction crew we can testify that in the rush and excitement of keeping up with the crew setting logs around the building, the individual or crew whose job it is to place the caulk or gasket may fall behind. It's easy to place and fasten down a log without noticing that the spline or gasket was omitted.

A little less common but still a problem among first-time log home builders is the omission of a T-jamb, splines or gaskets at window and door openings. Our ruler is being used to probe behind the window jamb to see if there was a spline or T-jamb used. (There was none.)

It is inherently tricky to mate a flat or rectangular window frame into a scalloped-surfaced log wall without leaks. Our photo shows use of a flat steel ruler as a probe to demonstrate that a flange, gasket, or even caulk were all omitted between this log wall window frame and the butt ends of the logs at the window rough opening.

But like most construction problems, the solution is well-known and at hand. Traditional log home windows and doors in Norway, for example, are constructed by placing a let-in rectangular board against the butt-ends of the logs at the window sides.

In the U.S. kit homes and manufactured milled log home designs typically include a "T-jamb" using a spline and rabbet grooved window jamb (or frame) to provide a positive seal (along with gaskets or caulk) between the window frame and the sides of the window opening where the butt ends of logs are exposed. Head flashing kits and sill flashing kits may also be provided by the manufacturer.

An outdoor view of the leaky log building wall at this window can be seen at Log Checking or Splitting.

Paul and we also used vertical braces nailed back to the floor deck and huge C-clamps along with levels, tape measures, eyes, string, other methods to keep our rapidly-rising log walls plumb and square. Log houses go up fast once everything is ready at the site.

If you do not keep an eye on your log walls during erection, unlike a platform-built wall that is constructed flat and lifted into place, it's possible for log walls to curve or lean out of plumb.

Our photo (left) shows a wall that was 7/8" out of plumb over 6'8 in height at a log home inspection (not one we built).

Out of plumb log walls on a home may also mean hard to seal intersecting building surfaces.

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