Splicing Pre-Engineered Wood I-Joists
Splicing Pre-Engineered Wood I-Joists
(OP)
We have encountered some severely deteriorated wood I-joists. The deterioration is due to water infiltration. The existing joists support residential loads and span approximately 20 - 22 ft. The deterioration is restricted to about 16" at one end of the joists, the remainder of each joist is in excellent condition.
Various options are being contemplated at a preliminary stage. Wholesale replacement of these joists would require an inordinate amount of work due to site conditions, etc... Providing a line of new intermediate support is being contemplated, which will allow the ends of the deteriorated members to cut and replaced with short new members, both bearing on the intermediate support beam/wall.
The third option being contemplated is trimming off the deteriorated ends and splicing the 16" end, along with an 8ft to 10ft splice length. The splice would include A) packing the webs both sides to the full width of the flange for the full splice length and B) sistering full depth dimensional lumber each side of the joist for the full splice length. The splice location would be in a low bending, high shear area of the span. Has anyone completed a similar type repair? Any comments or suggestions conceptually before we start putting some numbers to this concept? This is not my preferable option, however, site conditions are very restrictive and if this can be made work, it will be the most constructable option of the bunch.
Various options are being contemplated at a preliminary stage. Wholesale replacement of these joists would require an inordinate amount of work due to site conditions, etc... Providing a line of new intermediate support is being contemplated, which will allow the ends of the deteriorated members to cut and replaced with short new members, both bearing on the intermediate support beam/wall.
The third option being contemplated is trimming off the deteriorated ends and splicing the 16" end, along with an 8ft to 10ft splice length. The splice would include A) packing the webs both sides to the full width of the flange for the full splice length and B) sistering full depth dimensional lumber each side of the joist for the full splice length. The splice location would be in a low bending, high shear area of the span. Has anyone completed a similar type repair? Any comments or suggestions conceptually before we start putting some numbers to this concept? This is not my preferable option, however, site conditions are very restrictive and if this can be made work, it will be the most constructable option of the bunch.





RE: Splicing Pre-Engineered Wood I-Joists
RE: Splicing Pre-Engineered Wood I-Joists
Mike McCann, PE, SE (WA)
RE: Splicing Pre-Engineered Wood I-Joists
Can't quite find it as of now, but I'll ask around once the other eng'rs start rolling in.
EDIT: 4:31PM Jun23 - Senior engineer forgets the name of the report too. I put a call into our Sr Wood guy and Im sure he can give me the name of the report. Sorry for the delay.
RE: Splicing Pre-Engineered Wood I-Joists
Signious, I am in Southern Ontario, therefore a report from Southern Alberta would be very interesting.
We are starting to put numbers to a splice detail and think we can work out something reasonable. It's worth it to throw a bit of extra wood and fasteners at it given the localized extent of the repairs.