Prior to installing a pre-hung door in your house, make sure that its framing is straight and level – at least 3/8 in out from plumb on trimmer studs if possible.
Use a hand level on both the wall surface and trimmer studs around the door opening to test this assumption. If they don’t appear level, add shims under each side jamb until they do.
Preparation
Renovating the interior doors of your home can increase security, define room boundaries and add curb appeal. To save both money and installation time, consider opting for pre-hung doors over slab ones; however, this project should only be undertaken by those with basic carpentry knowledge and skills.
Begin by dismantling the old door using a screwdriver and hammer. Take care to unbolt any hinge pins or strike plates before prying out its casing to reveal it.
Measure the rough opening and sill area. If the opening is larger than necessary for your new door, use shims to reduce gap width. Check that the frame is plumb and square by using a level and tape measure; nail any necessary shims to the frame/studs as required to correct deviations from this.
Measurements
Prior to hanging a door, it is essential that measurements of its rough opening be taken. This ensures that it fits securely and swings easily when installing.
To accurately gauge the height of an opening, take measurements from the top part of the frame down to its base near its right end and record both measurements – one on either side will give an accurate reading.
Measure the width of your rough opening using a 4-foot level placed on the floor in your doorway. If this level strays more than half an inch out of plumb, you must shim both hinge sides and latch sides first before proceeding further with adjustments to frame sides.
Shims
Use wood shims (thin pieces of tapered wedged wood) to fill any gaps between the frame and studs on the hinge side of your door opening, and leveling head jamb with wall surface and studs on trim side – then double check using plumb bob or level to ensure it’s square.
Once both head jambs of your doorway are level and plumb, nail through shims to secure its frame flush against the wall. Check that your reveal is uniform as you close and open it – if not, shim the other side and repeat. Additionally, remember to shim where the bottom of the door meets its frame as well.
Nails
Modern interior doors come either slab or prehung options. Prehung doors provide a complete package that comes equipped with hinges attached to their frame, including doorknob holes in their frames as well as features like thresholds that help keep out drafts, pests, and water.
Advantages to this type of door include saving time and labor when compared with building one from scratch; however, its drawbacks include being more costly upfront and being very heavy, sometimes up to 100 lbs in weight! Therefore it is crucial that proper planning be put in place and assistance obtained for moving such heavy objects around if required; additionally they tend to limit design options due to being visually standardised.
Caulking
Fill any gaps between the new door and frame using paintable caulk, making sure it dries completely before installing additional hardware.
Prehung doors can save time and effort while adding energy efficiency, safety, and security features to your home. Most home centers and lumberyards sell them.
Before installing your new door in its opening, use a carpenter’s level and tape measure to check that its frame is square with itself and plumb. If necessary, adjust by shimming as necessary; drive galvanized casing nails through shims into framing starting from hinge side around to latch side shimming as necessary.