Patching a Large Hole in Drywall

An operation of correcting a large hole (more than a foot in wide) in a drywall section takes special tools in addition drywall compound, tape and broad knives. But performing a single large patch should be approached somewhat differently than the patching multiple large drywall holes .

For cuts and cleanouts - expose the new opening for bracing at 2 studs or beams if possible (splitting the bracing up with existing bordering sheets). Do the cutout by the guide of a T square or straight edge markings and make the cut with a drywall router if possible. Be sure to remove any weakness or loss of wallboard integrity from hole impact. And give the gypsum a quick hit with a rasp in order to clean the lines (the larger the piece, the greater is the general need for cut-line correcting).

Drywall screw perimater backing around the cutout perimeter (wood strips or plywood). Have plastic sheeting placed beneath areas of work and vacuum for dust as you go since it can move with stealth and quickly accumulate into unwanted areas.

For the finish cuts on the wall side: since you are using the new drywalla cutout as a wall template, the cutout itself should be sized at right angles, either square or rectangular. And the measurement transferred onto the hole punched wall to make the cut.

A word on positioning the patch: double check the measurements of the new replacement with that of the wall to make sure it will form a comfortable fit. This will prevent repeated cuts and placements, resulting in fewer moves.

For patches of large hole sections at or near the floor-level, rig a prybar onto top of a waste drywall strip to leveer into position the new large replacement with this lift (note that the baseboard may need removing - and the new wall section should meet up with the same concealed wall level, on its lowest edge, for casing support)

A word on drywall storage: store the big pieces of drywall flat on a level surface to prevent warping - the bending can appear overnight.

For replacement at ceiling level a panel lift/hoist can typically extend the piece 11 foot on the horizontal. Many models can be operated by a single person.

Fasten with screws, both on the new and existing drywall sections. Tape with preferred mesh or paper, and knife on the mixed mud.

A word on larger patch mudding: increasingly broad knives become important the more sizable the patch or aged the structure (speaking of wall contours, due to settling, or crooked framing). An exterior door replacement that becomes a new drywall section that must be matched with the surrounding interior drywall surface, would best be made undectable as a patch by floatomg the mud off with 10" or 12" broad knife over spans of dips, rises and traverses. And as a rule, the larger the patch, the more passes that should be taken with the compound.

Following sanding, seal with drywall primer for surfaces to be painted with oils and/or higher gloss and for areas exposed to moisture.