Residential Attic Loads

Spans for ceiling joists shall be in accordance with tables r802 4 1 and r802 4 2.

Residential attic loads.

Dead load of attic floor when floored 20 lbs. Of floor area dead load on second floor 20 lbs. Of floor area dead load of partitions 20 lbs. Minimum uniformly distributed live loads adapted from sei asce 7 10.

0 9d 1 0w a load factor of 1 6 when adding to load 7. 2attic loads may be included in the floor live load but a 10 psf attic load is typically used only to size ceiling joists adequately for access purposes. Dead load of attic floor not floored 10 lbs. Offices require 50 psf.

For example if building is 24 x 24 and has trusses and the load on the roof will be for 30 lb snow load and a ceiling with no storage will total out like this. Buildings with combustible ceiling or roof construction shall have an attic access opening to attic areas that have a vertical height of 30 inches 762 mm or greater over an area of not less than 30 square feet 2 8 m 2 the vertical height shall be measured from the top of the ceiling framing members to the underside of the roof framing members. 0 9d 1 0e effect or 0 9 when resisting the load when permanent. Loads should be determined in accordance with this chapter.

The minimum live loads provided in table r301 4 are the minimum loads which must be applied in the design of each of the elements listed. It brings together all building plumbing mechanical fuel gas energy and electrical provisions for one and two family residences. However if the attic is intended for storage the attic live load or some portion should also be considered for the design of. Minimum design loads for buildings and other structures location uniform load psf kn m2 apartments see residential access floor systems office use.

In sleeping only areas a 30 psf live load is required. Attics constructed to include storage space must be designed for 20 psf live load. Storage space dead load of partitions 20 lbs. Other residential rooms 40 psf.

For other grades and species and for other loading conditions refer to the awc stjr. Table r802 4 1 ceiling joist spans for common lumber species uninhabitable attics without storage live load 10 psf l δ 240.