One New Thing

I am an architectural designer. I learn something new every day.

[one-new-thing]

Today I learned that, per my co-worker:

A project manager is responsible for budget, schedule, etc: basically running the project itself.

A project architect is responsible for code compliance, details, completeness: basically making sure design requirements are met. Focus on construction documents.

A project designer is responsible for the overall look of the building or design. Focus on schematic design.

Of course, depending on the size of the firm and the project, one person may end up wearing all these hats.

[one-new-thing]

Today I learned that skip sheathing, otherwise known as spaced sheathing, is roof sheathing that instead of being a solid panel of plywood or OSB, is 1x4s spaced 4" apart. This sheathing is used under wood shake roofs to allow the shakes to dry out.

When reroofing with a different material, the new sheathing can be installed right over the skip sheathing if it's not rotted.

[one-new-thing]

Today I learned that a blocked diaphragm is a flat structural system in which all panel joints are attached to framing or blocking. For example, a section of floor in which blocking is nailed between all joists and all subflooring edges are nailed to those blocking units, creates a blocked diaphragm. A blocked diaphragm can carry much more load than an unblocked diaphragm, and is often used as part of a system to resist lateral loads such as wind or earthquakes.

[one-new-thing]

Today I learned that the technical definition of an entitlement (in terms of property) is:  the legal method of obtaining approval for the right to develop property for a particular use. So, the entitlements portion of a project is the part that involves getting those approvals (permits, variances) from the city or other planning department.

[one-new-thing]

Today I learned about waterstops. A waterstop is a seal placed at a joint in concrete (construction joint, control joint (for shrinkage) or isolation joint (for walls and columns.)

Two types of waterstops:

Mechanical

Made of a flexible waterproof material: PVC or rubber

Come in a variety of shapes to suit different types of joints

Are embedded in concrete: Fastened to rebar or form ties before concrete pour

Adhesive

Only for construction joints

Come in long strips; installed with splices kneaded together

Installed on first poured concrete before second pour, so embedded in second pour

[one-new-thing]

Today I learned that [FS] stands for waterflow switch, or flow switch: a switch that alerts the fire alarm system when it detects water movement or a change in water pressure in the sprinkler system.

Electrical - plumbing - fire safety coordination item.

[one-new-thing]

Today I learned that [TS] stands for tamper switch: a switch that alerts the fire alarm system when a manual cutoff valve in a sprinkler system is closed.

Electrical - plumbing - fire safety coordination item.

[one-new-thing]

Today I learned that CSP stands for combined standpipe line: a riser that both functions as a standpipe and provides water for sprinklers.

Must be a wet standpipe system.

[one-new-thing]

Pro Forma

Today I learned that a pro forma is a description of the projected cost and financial return of a proposed real estate development. It's a tool for summarizing the feasibility of a proposed project or deal. Basically it will include enough information on costs, revenue, expenses, and financing to answer the question: what needs to happen in order for the proposed development to bring in more money than it costs to build?

See also:

An introduction and fairly detailed explanation

A simple PDF example

A sample pro forma Excel spreadsheet from the Dept. of Housing & Urban Development (see sheet 2)

An idiosyncratic commentary with a lot of clip art

[one-new-thing]

Today I learned that Douglas Fir and Western Larch are interchangeable species in dimensional lumber, so may be specified just as “Douglas Fir Larch”.

[one-new-thing]

Today I learned that in mid-rise buildings (no one knows what mid-rise means) an Anchor Tiedown System (ATS) can be used to prevent shearwall overturn instead of more basic hold-downs. For more information about shear walls see McVicker.com, or if you prefer to learn from spray paint on the side of a cow, learningconstruction.com.

[one-new-thing]

QSELECT

Today I learned that the QSELECT command in AutoCAD is a lot more versatile than I had realized. I've often used it to select everything on a layer; but you can also use it to select every instance on a block (and then pull up the PROPERTIES tab, for example), every polyline of a given width, every mtext of a given text height...it's a very powerful command!

[one-new-thing]

hat vs. z

Today I learned that if furring out >2" you should use a hat channel instead of a z channel.

[one-new-thing]

Rainscreen

Today I learned that a rainscreen is a wall system which includes an air gap between the exterior cladding and the moisture/vapor barrier. It must have drainage holes at the bottom and probably ventilation gaps at the top to allow for convection-driven airflow through and drying of the wall structure.

The idea is that water is going to get into your wall no matter what you do; a rainscreen provides it a way to get out, rather than stay in your wall forever encouraging black mold.

[one-new-thing]

Thermoset-thermoplastic

Today I learned that a thermoset plastic changes state permanently upon the application of heat, whereas a thermoplastic material can be reheated and reshaped.

[one-new-thing]

Kynar

Today I learned that Kynar is a resin included in both powder coatings and paints; good for metals, good for corrosion and weathering but not recommended in high-traffic areas.

[one-new-thing]

San Francisco Housing Action Coalition

Today I learned about the San Francisco Housing Action Coalition and their opinion on Jane Kim’s proposed increase from 12% to 25% required affordable housing. Instead, they support the Affordable Housing Bonus Program, which basically means you can add two stories to your building if you include affordable housing. Which in a city as height-phobic as San Francisco, is something.