Residential roof-truss erection from an exterior top plate

August 23, 2004

MEMORANDUM FOR:

RICHARD S. TERRILL

REGIONAL ADMINISTRATOR REGION X

ATTN:

DALE CAVANAUGH

FROM:

RUSSELL B SWANSON, DIRECTOR

DIRECTORATE OF CONSTRUCTION

SUBJECT:

STD 03-00-001: Fall protection when working on exterior top plate.

This is in response to your e-mail submitted March 31, 2004. You requested that OSHA address whether, under STD 03-00-001 [formerly STD 3-0.1A], employees may walk on the exterior top plate without using conventional fall protection when installing roof trusses.

We have paraphrased your question as follows:

Question: May an employee installing roof trusses walk on the top plate of exterior walls without fall protection or is the procedure stated in STD 3-0.1A Section (IX)(B)(1)(b)(2) limited to walking on the interior top plate?

Answer: STD 3-0.1A provides alternate procedures to the conventional fall protection requirements in 29 CFR 1926.501(b)(13) for certain types of residential construction. Section (IX)(B)(1)(b)(2) of the directive states the procedures for working on the top plate as follows:

(a) Installing The First Two Trusses

The first two trusses/rafters must be set from ladders. The ladders must lean on side walls at points where the walls can support the load imposed by the ladder and worker. After the first two trusses/rafters have been set, a worker will climb a ladder onto the interior top plate to secure their peaks.

(b) Remain On The Top Plate

Workers will remain on the top plate and use the previously stabilized trusses/rafters as support while the other trusses/rafters are erected.

Under the terms of these provisions, employees are not permitted to work from the exterior top plate when installing roof trusses. STD 3-0.1A establishes a specific procedure for installing roof trusses. It requires that the first two trusses be set from ladders and that the employees setting the trusses then climb onto the interior top plate to secure their peaks. The workers are then to "remain on the top plate and use the previously stabilized trusses/rafters as support while the other trusses/rafters are erected." [Emphasis added.]

The Directive thus states that the employees must climb from the ladder onto the interior top plate, and remain on that top plate - which is an interior top plate. No mention is made in the directive of working from an exterior top plate, which, therefore is not permissible.

If you need any additional information on this matter, please contact us by fax or e-mail.