Residential Attic Loads

The load on an outside wall with clear span trusses is exactly half the load on each wall.

Residential attic loads.

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. Offices require 50 psf.

0 9d 1 0w a load factor of 1 6 when adding to load 7. For other grades and species and for other loading conditions refer to the awc stjr. Dead load of attic floor when floored 20 lbs. Loads should be determined in accordance with this chapter.

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. Table r802 4 1 ceiling joist spans for common lumber species uninhabitable attics without storage live load 10 psf l δ 240. Minimum uniformly distributed live loads adapted from sei asce 7 10.

Other uses for attics and lofts include a live load plus a 10 psf dead load for the weight of the floor support system floor sheathing sheetrock on the underside and any insulation. 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. Dead load of attic floor not floored 10 lbs. Spans for ceiling joists shall be in accordance with tables r802 4 1 and r802 4 2.

Code for residential buildings that creates minimum regulations for one and two family dwellings of three stories or less. Of floor area dead load of partitions 20 lbs. In sleeping only areas a 30 psf live load is required. Minimum design loads for buildings and other structures location uniform load psf kn m2 apartments see residential access floor systems office use.

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. Of floor area dead load on second floor 20 lbs.