Thursday, August 30, 2012

Getting A Free Blower Door Test

Here is an example of the conflict of interest war against a home owner's interest, sponsored by HPwES, channeled here through an arm of Energy Trust of Oregon, Clean Energy Works Oregon. I think there is a similar thread in most big cities. (This cost my HPwES competitor, by my clicking on his offending Google ad.)

Sign up with him for the useless free blower door test, and you're stuck with him, whatever he offers, and does or does not do.

More Freshly-Minted Building Science Professionals

I am able to recall and report something that offended me yesterday, with help of Google. Search "bpi certification 100% Pass".

There it is:

Congratulations Jan. 2012 Dual Cert class held at John Logan College, Carbondale, IL for a 100% written exam pass rate for both certifications!!!!!!!!! 10 students - 20 exams - 100% !!!!!!!

Maybe ten extraordinary wits, though dumb enough to pay $40 per hour for the fruitless knowledge-stuffing, twice the hourly rate of competent state university education.  The diploma mills are everywhere. The high pass rates are everywhere, evident in other findings of the Google search. So much money pouring to BPI.

Friday, August 17, 2012

More T91 Plate LED Light Installation Examples

Please consult this Picasa Web Album:

Here is the finished result over a kitchen sink.
I think the 6" T91 is comparable to a 100 watt incandescent bulb, and will prove too bright for some preference. This, although packaging says equivalence is to a 75 watt incandescent bulb. 

A 4" version of this LSGC Glimpse light exists, and when offered at consumer pricing, will fit on the same junction box.

The 6" luminaire was released in Home Depot stores in September 2011. I suggest that a T91 price reduction from $37.97, to $29.97, at end-August 2012, is with imminent release of the 4" luminaire.

Monday, August 6, 2012

Ventilating A Residence Attic

A home well-built in 1990, was with thoughtless attic ventilation. Repairs of soffit inlets are presented in a Picasa Web Album. Here are some of the photos.

Most plywood baffles were fully pinched against roof sheathing. Provide access, and repair within the attic. Let minimum path area be at the inlet screens.

Enlarge slots from outside. Knock off points with a chisel. Clean out another bird's nest, not observed from the attic.

The inlet area of this 650 sq ft attic is increased from 0.6 sq ft, to 2.2 sq ft. Exhaust area remains 2.2 sq ft. 

A minimum ventilation area goal for this attic size, as expressed by Joe Lstiburek, is 2.2 sq ft total, 1.3 sq ft in eaves inlets, and 0.9 sf in peak exhaust. The rule is 1 sq ft total for every 300 sq ft of attic area, minimum, split 60%, 40%.  A well-ventilated attic should have double these areas, in still the 60/ 40 split. I should increase the inlet area further, before any increase of exit area. Without a large increase of inlet area, there must be no powered attic ventilation, even though I carefully sealed the attic floor, reaching through all that loose-fill.

Sunday, August 5, 2012

Attic Ventilation, Thoughtful In A School Building

On one of the few hot days of Summer 2012 in Metro Portland Oregon, I noted interesting ventilation of the attic of Lake Grove Elementary School. Features afforded in municipal buildings can inspire residential construction.

Ventilation exhaust is via pretty copper cupolas, and by continuous roof peak vents. Each cupola will be custom built by a craftsman. Copper By Design,  serving Portland, and anywhere, notes the copper controls moss. Extended roof life will cover much of the copper fabrication cost.

Surely there is a reason soffit vents are not larger. Construction can be thoughtless of ventilation, with negligible flow paths above the soffits.

A porch ceiling at the grand-parenting scene of a nice playground provides much of the entering air capacity. I hope there are similar ceilings around the buildings. I do not accept the lore of the advocates of soffit vents, that inlet air paths must always be evenly distributed. I think air is screaming through this screen, and turbulence cools the entire attic.