Gypsum Wallboard (Drywall)
Gypsum wallboard is not required throughout a dwelling however it is widely used as an interior finishing material. Gypsum wallboard is required:
- On the garage side of the wall between the house and garage.
- In enclosed accessible space under stairs.
- On a wall of a building less than 3 feet from a property line.
- For separations between dwelling units where two or more dwellings exist in the same building.
The State of Minnesota has updated the building code effective January 24, 2015. We are in the process of reviewing our website to make sure everything is up to code, but you should always review the State of Minnesota Building Code before beginning any project.
- Gypsum board may not be installed until adequate weather protection is provided. Gypsum wallboard intended for interior use may not be used in areas exposed to the weather.
- Interior non-bearing studs may be 2 by 3 studs spaced not more than 24 inch on center (OC). Exterior or bearing walls must be 2 by 4 minimum and spaced not more than 24 inch OC.
- Other framing supporting gypsum board, such as for soffits or furring, may be 2 by 2 material. If the furring is applied against a solid backing such as foam sheathing on a foundation wall, it may be 1 by 2 material.
- All edges and ends of gypsum wallboard must occur on framing members except those edges and ends that are perpendicular to framing members. All edges and ends of gypsum wallboard should be in moderate contact except in concealed spaces where fire resistive construction or diaphragm action is not required.
You can not use 3/8 inch gypsum board on a ceiling in either of the following situations:
- Where a water-based textured finish is to be applied.
- Where it will be required to support insulation above a ceiling.
On ceiling applications that will receive a hand or spray applied water-based textured finish:
- Gypsum board must be applied perpendicular to the framing.
- 1/2 inch gypsum board must be used for 16" OC framing.
- 5/8 inch gypsum board must be used for 24" OC framing (½" sag-resistant gypsum ceiling board may be used as an alternate).
Moisture Resistant Gypsum Board
Regular gypsum wallboard may not be used as a backer for tile or wall panels for tubs or showers. Moisture resistant gypsum board or other approved materials must be used in these locations.
Moisture resistant gypsum board may not be used in the following locations:
- Over a vapor retarder
- In areas subject to continuous high humidity such as saunas or steam rooms
- On ceilings where frame spacing exceeds 12 inch for 1/2 inch gypsum board and 16 inch for 5/8 inch gypsum board
Cut or Exposed Edges Must be Sealed
All cut or exposed edges, including those at wall intersections, must be sealed as recommended by the manufacturer.