Wrinkly Tyvek – A Report

East wall tyvek2

This is DuPont Tyvek Drain Wrap commonly know as “wrinkly” Tyvek. In previous installations, we’ve used regular smooth Tyvek and battens to create the drainage plane behind the siding. This wrinkly product promises to create the drainage plane without the battens.

This post reports on what we encountered:

We wrapped Bituthene around the framing before the windows were installed. Some of the windows had nail fins, and some didn’t. The windows that didn’t got fabricated sheet-metal pans sloped to drain. DR window flashing2Note the sheet metal is Rezi-Bond, galvanized metal coated to promote paint adhesion.

We foamed the gaps between the windows and the studs. Where the foam oozed out, we trimmed it off carefully with a serated kitchen knife. The Tyvek carried over the Bituthene, over the foam, and turned out at the window. Then the trim boards and corner boards were pre-caulked and nailed over the Tyvek.

It’s hard to get it to lay flat! Wrinkly means wrinkly and the installation looks amateurish; it fans out, won’t stay level, and won’t lay down nicely. All that said, it shouldn’t make any difference to how it performs.DR window tyvek3

We’re installing Hardie plank in the 8″ Colonial pattern. You can see the slight indentation that transforms regular Hardie siding into “Colonial” siding. We had to order it in smooth in lieu of wood-grained and it costs slightly more,  but it’s worth it; when it’s painted, from fifty feet away, if you squint, it almost looks like the original wood siding.

The story board is tacked onto the trim. Note that the marks on the story board control the top of the siding which is hidden by the succeeding layer.starter strip

To get the first course of siding to lay at the same angle as the succeeding courses, we use starter strips. These are cut from 4×8 sheets of cored poly-styrene that we get from the sign shop. The cores allow the drainage plane to drain, but keep the bugs out.

Knauf Eco-Seal – A Report

Knauf Eco-Seal in Richmond
We’re working on a little house on Terrace St. It’s a 1902 railroad worker’s cabin on the hill looking out over the Richmond train yard. photo from wall touchedBoards nailed to boards, no studs, with a layer of newspaper to slow down the wind blowing through. Saturday, January 4, 1902 was when the old guys built that particular piece of wall. (Note: the Walla Walla actually sunk on Thursday the day after New Years day, but it wasn’t reported in the papers until Saturday.) The original work is so rough, the little house may have been an amateur weekend project, hence the Saturday paper!

It’s a duplex, the upper half is fairly intact as the original cabin, the lower half is getting a complete remodel; as energy efficient as we can make it on a limited budget.
Bucket IIWe couldn’t afford the $4.00/s.f. cost of spray-in foam, so we decided on a compromise between foam and newspaper: a product from Knauf called Eco-Seal. The claim is that Eco-Seal will stop the air infiltration, and fiberglass batts or blow-in will provide the insulation. The advertising says “Simple airless equipment”, as opposed to specialized equipment for spray-foam costing $20K or more.

Well, we’ve got an airless, so we bought a bucket of the Eco-Seal – $225.00. One thing for sure about Eco-Seal; it’s blue! We put the intake in the bucket and fired up the airless. Nothing. The intake wouldn’t begin to pick up the thick blue material. When we finally read the fine print, it says the airless has to be a “Graco 695 or equivalent”. This is a one gallon-per-minute machine, and none of the rental yards in the Bay Area have one that big.
Kelley Moore in SSF came to our rescue; it’s a long trip from Richmond to SSF, but worth it?
Intake tubeThe intake tube on the 695 wouldn’t pick up the heavy material either. We finally took off the tube and set the machine right in the bucket.



Airless in bucket

We blocked the bucket up so the intake was picking up off the bottom. Even so, it tended to suck wormholes in the blue material and cavitate the pump.





Moving goo to pickupWe had to take a shingle and keep pushing the Eco-Seal material over towards the pump intake.





All this manipulation in the open bucket made a mess and caused extraneous bits of material to fall in, so the spray tip kept clogging. It took two hands to run the gun, one hand on the trigger and the other on the tip to reverse it every two feet or so to blow the clogs out.Reversing tip

This was a pain in the neck, we never would have gone to this much trouble, but we’d spent the $225.00 for the Eco-Seal, if it works, it will do what nothing else will. When it works, it foams up just enough to make a nice bead, and it looks convincing as an air infiltation stopper. Only the blower door test will tell.

The silly part is that the airless may be unnecessary. The folks that build log homes have miles of gaps between the logs to caulk neatly. They’ve developed a set of manual tools to install bulk caulk out of five gallon pails which I’ll bet would work very well for the Knauf product. It’s what we’ll try next time.

Here’s the company video:

Demand-Responsive Parking in San Francisco

Demand-Responsive Parking in San Francisco

 This article first appeared on the website THINKPROGRESS

By Matthew Yglesias on Aug 11, 2010 at 1:44 pm

People generally understand that there were shortages and long lines for things in the Soviet Union because goods weren’t priced according to supply and demand. And people generally understand that, in general, price controls will tend to lead to either gluts or shortages. And yet few people understand that this same principle applies to on-street parking. In many places, it’s hard to find and that’s because it’s not priced properly. San Francisco is trying to change things with its SFPark initiative:

SFpark will charge the lowest possible hourly rate to achieve the right level of availability in both garages and at metered spaces. This project is not about raising parking revenue; it’s about making parking easier to find. SFpark is designed so each block and each garage maintains have about, an average, 20% availability. [...]

SFpark will use demand-responsive pricing to even out parking availability and reduce the need for circling. In pilot areas, meter pricing can range from between 25 cents an hour to a maximum of $6.00 an hour, depending on demand. During special events, such as baseball games, hourly prices may temporarily increase beyond the $6.00 ceiling. Parking rate changes will also affect City-owned garages and lots in pilot areas. Since many City-owned garages are currently underutilized, the prices are likely to decrease, which will attract more parking demand to City garages.

A nice next step would be for the city to get out of the garage-owning business. In a city where street parking is priced in a demand-responsive way and developers are not subject to regulatory mandates to construct parking, one assumes that parking garages and parking lots will still be constructed. If you want to drive somewhere then you’ll need to park your car, and since people often do want to drive there’s money to be made charging them for the privilege. But regulatory mandates and city-owned garages tend to ensure that parking is oversupplied.