2026 IRC EXAM - IRC CHAPTER 5 – FLOORS
QUESTIONS WITH CORRECT ANSWERS
2025
A minimum design load of _________ shall be used for the determination of the maximum allowable flo
or joist spans in attics that are accessed by a fixed stairway. - correct answer-30 psf
Where not supported on a ribbon strip, the ends of floor joists shall bear a minimum of _________ on w
ood or metal. - correct answer-1 1/2 inches
R502.6 Bearing
Floor cantilever ratio of back span to cantilever span:
- where supporting a bearing wall and a roof: _____:_____
- where only supporting an exterior balcony: _____:_____ - correct answer-3:1
2:1
R502.3.3 Floor cantilevers
For cantilevered floor joists, regardless of loading conditions a maximum span equal to the ______ is per
mitted. - correct answer-depth of the floor joists
R502.3.3 Floor cantilevers
Where piping or vents penetrate the floor system, joists may be ________ and ________ to allow the pip
e or vent to pass through. Solid blocking between the joists at _______ ſt intervals is required so that the
two joists will function as a combined member without twisting. - correct answer-doubled
separated
4ſt
R502.4 Joists under bearing partitions.
, Rim joists can be braced laterally by ______ _________ or _______ ________ at the end points and spac
ed at intervals of ________ feet. - correct answer-solid blocking
diagonal bridging
8ſt
R502.7 Lateral restraint at supports
Draſtstopping shall be installed ___________ to floor framing members, unless approved by a building of
ficial. - correct answer-parallel
R502.12xDraſtstopping.
Concretexslab-on-
groundxfloorsxrequirexax______xinchxthickxgravelxbasexcoursexwherexthexslabxisx________x_________
.x-
correctxanswer-4xinch
belowxgrade
(exceptionxifxslabxisxonxwell-drainingxsoils)
R506.1xConcretexslab-on-groundxfloors.
Reinforcementxforxslabs-on-
groundxshallxbexsupportedxtoxremainxinxplacexduringxthexconcretexplacementxfromxthex_______xtoxthex
__
_____x________xofxthexslab.x-xcorrectxanswer-middle,xupperxthird
R506.2.4xReinforcementxsupport.
Deckxverticalxloadsxshallxbextransferredxtox________x__________xwithx_________.x-
xcorrectxanswer-
bandxjoists,xledgers
R507xExteriorxdecks.
QUESTIONS WITH CORRECT ANSWERS
2025
A minimum design load of _________ shall be used for the determination of the maximum allowable flo
or joist spans in attics that are accessed by a fixed stairway. - correct answer-30 psf
Where not supported on a ribbon strip, the ends of floor joists shall bear a minimum of _________ on w
ood or metal. - correct answer-1 1/2 inches
R502.6 Bearing
Floor cantilever ratio of back span to cantilever span:
- where supporting a bearing wall and a roof: _____:_____
- where only supporting an exterior balcony: _____:_____ - correct answer-3:1
2:1
R502.3.3 Floor cantilevers
For cantilevered floor joists, regardless of loading conditions a maximum span equal to the ______ is per
mitted. - correct answer-depth of the floor joists
R502.3.3 Floor cantilevers
Where piping or vents penetrate the floor system, joists may be ________ and ________ to allow the pip
e or vent to pass through. Solid blocking between the joists at _______ ſt intervals is required so that the
two joists will function as a combined member without twisting. - correct answer-doubled
separated
4ſt
R502.4 Joists under bearing partitions.
, Rim joists can be braced laterally by ______ _________ or _______ ________ at the end points and spac
ed at intervals of ________ feet. - correct answer-solid blocking
diagonal bridging
8ſt
R502.7 Lateral restraint at supports
Draſtstopping shall be installed ___________ to floor framing members, unless approved by a building of
ficial. - correct answer-parallel
R502.12xDraſtstopping.
Concretexslab-on-
groundxfloorsxrequirexax______xinchxthickxgravelxbasexcoursexwherexthexslabxisx________x_________
.x-
correctxanswer-4xinch
belowxgrade
(exceptionxifxslabxisxonxwell-drainingxsoils)
R506.1xConcretexslab-on-groundxfloors.
Reinforcementxforxslabs-on-
groundxshallxbexsupportedxtoxremainxinxplacexduringxthexconcretexplacementxfromxthex_______xtoxthex
__
_____x________xofxthexslab.x-xcorrectxanswer-middle,xupperxthird
R506.2.4xReinforcementxsupport.
Deckxverticalxloadsxshallxbextransferredxtox________x__________xwithx_________.x-
xcorrectxanswer-
bandxjoists,xledgers
R507xExteriorxdecks.
