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What species of lumber are specified on your plans?

Sawn lumber species are typically Douglas fir, or Hem–fir. Substitution of material (species or grade) should not be undertaken without the review of a qualified professional, as required by your local building codes and ordinances. Many lumber yards have staff that are versed in substitution of material, and can work from the load information contained in our calculations, to determine the proper replacements.

What design load values are used in the gravity calculations you provide?

The structure has been evaluated with Roof Live Load of 30psf, Floor Live Load of 40psf, Live Loads of 15psf, and Soil Bearing Pressure of 1,500psf. Otherwise, design loads follow the current I.R.C. code book. Calculations using different design values require additional time and fee. It is best to enlist the services of a local professional for such “location–specific” structural redesign. Local lumber yards sometimes have contacts for such services.

How about beam calculations, do you provide these?

Yes, we can provide vertical gravity load calculations per your request, free of charge. These calculations do not carry a stamp from an engineer. Again, if an engineer’s stamp is required, you will have to make the appropriate arrangements, and allow for the added time and expense involved.

How do Spokane House Plans address high wind and seismic design criteria?

Our stock plans require additional structural information and detailing in order to meet high wind and seismic requirements, which vary by geographic location and legal jurisdiction. For an additional fee, we can provide engineering to meet specific seismic zone, wind speed and wind exposure values for a specific building site. Such engineering analysis is site-specific and requires additional time to prepare. The drawings detailing this, and the supporting calculations, stamped by a licensed engineer are typically available for Washington or Idaho within a few days — check with our staff for availability in other states.

I’ve noticed many items, such as window brands, are left ‘generic’ on the plans; why is this?

These plans are not intended to be the only documents of construction. Items, such as mechanical, electrical, and plumbing layout, fixtures, and finish products, are matters of local construction practices or personal taste. Their detailed specifications are a typical function of the general contractor, and a usual part of the construction contract documents.

With which codes do your plans comply?

The plans, and associated documents have been prepared to comply with the latest adopted version of the International Residential Code (I.R.C.)

Each state in the US adopts a building code as their base code. Over the years, there have been several national code standards for states to choose from, but now the International Residential Code has become very widely accepted as the standard base code. For this reason, we choose to follow the I.R.C. in developing our plans. Unfortunately, each state can modify the base code with their own state adopted amendments, and may chose not to adopt certain sections of the base code. Energy requirements are a common section that is heavily modified or replaced by a different model code, by each state.

To further complicate the issue, the base code is revised every three years or so, and states vary in their timing of when they adopt each new code version – a year or more delay in adopting the latest code is very common. Beyond that – every local permit issuing jurisdiction within each state (counties, cities, etc.) can further amend the state requirements. Aware of this reality – our staff knows to never promise that our plans will be able to meet every requirement of every jurisdiction in the country. We do make every effort to comply with the national base code, and beyond that, we provide follow-up support to help our customers to meet the amended codes of their jurisdiction where possible.