Chapter 26: Interior Trim and Doors

1. Introduction

On most Habitat projects the Interior Trim, and doors can be completed during 1-2 scheduled workdays. This includes each of the items shown on the Order/Task list and, in most cases, the jobs are to be completed in the order listed. However, many of these tasks can be done simultaneously by different crews. In addition installation of the cabinet and hardware can be accomplished at the same time. As will be stated later, it is important to have experienced crew leaders for this phase, as the jobs require a lot of trouble-shooting for specific situations that will arise. If in doubt, consult the construction site coordinator.

2. Safety Issues

• Wear ear & eye protection when using power saws.
• Don't bind the blade of any saw.
• Keep electric cords out of the way of the saw.
• Don't cross hands over to stabilize material when using miter saw. Have someone else hold it for you.
• Remove nails from discarded material.
• Use extreme care and train operators when using nail guns

3. Prior tasks to have been completed before starting

Ideally the drywall should be finished and walls painted with at least one coat of primer and paint before starting to do the trim work. The ceilings can have two coats of paint on them.
Vinyl tile floor installed (and protected with plastic if possible)
If it can be coordinated, all trim (factory pre-primed typically) should be painted with one coat of finish paint before it's actually nailed onto the walls.

4. Recommended Staff/Crew Assignments

It is suggested that approximately 10 volunteers, including 2-3 crew leaders, be recruited for Interior Trim. Divide the crews up by distributing the experience level among the crew leaders. Each crew is then assigned to certain rooms or tasks.

Trim carpentry, as the name implies, is the work that is most visible in a house and must be done by the most experienced volunteer crews. Care should be taken to avoid excessive hammer marks on the trim material and all nail heads must be set below the surface. In addition, careful measuring and cutting helps to reduce the amount of waste on the job. Start cutting in the biggest rooms, as the "mistakes" can be used in the smaller areas.

6. Tools/Equipment list

Tools & Equipment Needed at Each Site:

• Twelve-Gauge Drop Cords (50'-100' as needed for power)
• Heavy-duty Power Strip
• Circular Saw ( 7¼")
• Saw Horses
• Electric Saber Saw
• Electric Miter Saw (10") with saw table
• Electric Drill
• 6’ ladder(s)
• Broom
• Caulking Gun
• Router and bit

Tools Each Crew Leader Will Need:

• 30' Measuring Tape
• 4' Level
• Cat’s Paw
• Pry Bar
• Wood Chisel
• Small Combination Square
• Sand Paper (100 grit)
• Nail Set
• Note Pad for recording dimensions
• Framing Square
• Chalk Line

Tools Each Crew Member Will Need:

• Hammer (16 oz. Min.)
• Nail Apron
• Retractable Utility Knife
• Measuring Tape (16' Min.)
• Speed Square
• 2 Pencils
• Safety Glasses
• Ear Protection

7. Material List

Nails/Screws/Fasteners (if not using nailgun)

• 4d Bright Finish Nails
• 6d Bright Finish Nails
• 8d Bright Finish Nails
• 16d Bright Finish Nails

Nails/Screws/Fasteners (if using nailgun)

• 2" finish nails
• 1-½" finish nailsSpacers/Shims
• Bundles of split shims Trim Components, etc.
• Interior split-jamb doors
• Baseboard
• Casing
• 1x6" primeboard(for windowsills)
• 1x8" primeboard (for stairway top)
• 4' Level
• Stair tread material (if not already installed)
• Stair handrailMiscellaneous
• Caulk (white latex)
• Spackle
• Construction adhesive

8. Quality Checkpoints

____ Doors properly hung: plumb, equal margins around doors, not hinge-boundbr>
____ No opened miter joints in casing, properly nailed
____ Joints in baseboard properly mitered or coped, properly nailed
____ Minimum gaps around windowsills in drywall openings
____ Nails set 1/16" below surface of all trim
____ All materials re-stacked, site cleaned, tools accounted for and put away

9. Construction Drawings and Text

NOTE: The following drawings, diagrams, and text are to be used on the job site when a question arises as to methods and procedures associated with the task. The notes on the drawings have been geared toward use as a quick reference. If a more in-depth explanation is needed, please read the text description. But most importantly, consult your Habitat Site Supervisor and Construction Manager for advice as needed.

1. General cutting and nailing instructions:

All interior trim joints (mitered or lap joints or coped corners) should be tight, with no space between the two pieces of wood. Good joints can be obtained by making accurate measurements and careful cuts. Do not use caulking or putty to “improve” a bad joint; simply re-cut or reposition the piece of trim.

Joints can be held more securely by applying a small amount of carpenter's glue (not caulk) to the two pieces before nailing. Also, small pieces of baseboard (between the edge of a door and the corner of a room, for example) can be attached to the wall with glue since even pre-drilled nail holes may still split the wood.

Attach interior wood trim by nailing through the drywall and into the house framing using appropriately sized finish nails as noted in the following sections. Drive finish nails only part way in (leave about ¼" exposed) to prevent hammer marks on the wood trim material and to allow the nail to be pulled in the event the trim needs to be adjusted to fit properly. If a nail must be pulled, cushion the hammer head with a block of wood to avoid denting the wood trim. After each piece of trim is properly installed, the nails can be driven the rest of the way in using a nail set. Set nails so the head is approximately 1/16" to 1/8" below the surface of the wood. Nail holes should be filled with wood putty prior to applying the final coat of paint.

2. Installing pre-hung interior doors:

Measure the rough opening and check the plan to insure that the proper sized door is being installed and that it will swing in the correct direction. The rough opening should be approximately 1½" to 2" wider and 1" to1½" higher than the door unit. Place the unit in the room where the door will swing when opened. If using split-jamb doors, separate the two halves of the split jambs, passing the small side through the rough opening. Use care to avoid damaging the mitered corners of the casing while separating the jambs.

With a crew member on both sides of the rough opening, place the jamb half with the door attached tight against the rough framing on the hinge side. (If carpet or underlayment and tile aren’t installed yet, place the door on a spacer made of 3/8" material. If underlayment and tile are already installed, set the unit directly on the floor.) Next, use a 4' level to plumb the hinge side of the door. Check the margin across the top of the door and, if the margin is correct, nail the upper corner of the hinge side casing (trim), after checking again for plumb. Holding the door plumb, nail through the lower corner of the hinge side casing. (If not using a split-jamb door, plumb and shim the hinge jamb and nail starting at the top near the hinge.) NOTE: If the margin at the top of the door is not even, you will need to raise one side of the casing to make it even. The hinge side can be raised, without pulling the first nail, by placing a flat bar under the casing and lifting it in position. The other side can simply be raised by sliding it up.

Since HFH St. Louis is typically using a split-jamb door, it is not necessary to plumb the lock side of the jambs. Simply hold the jambs so the margin on that side is the same from top to bottom, then nail through the casing at the upper corner, center and lower corner.

Check the door for proper operation. Make sure that the door is not hinge bound and that it makes contact with the doorstop at the top, bottom and center at the same time. Next, finish nailing through the casing, leaving the nail heads exposed. The nailing pattern is five nails, equally spaced, on each side casing and three nails across the top. NOTE: It is strongly suggested that the door be checked to make sure it is “in the plane”, “vertical” and “square” after every nail. If a problem is found using this method, its source is easily identifiable.

After nailing the casing on the main side of the split jamb, check the door again for proper operation and adjust as required. Next, install shims between the back of the door jambs and the rough frame opening at the top, bottom and behind the lock location on the lock side. Use a piece of ½" OSB when possible as this is sturdier than piling up split shims. When using split shims together, place them thick end to thin end. NOTE: Twisting the door jam when installing shims is the most common cause of hinge bind. Carefully insert the shims so as not to move or twist the doorjambs. The shims should be just tight enough not to fall out. After the shims are in place, but before nailing, check the door again for proper operation. Adjust the shims as necessary to eliminate the problems of binding the hinges or changing the margins around the door.

Nail through the doorjambs and through the shims, into the rough framing. Use one 8d finish nail at each shim location on the lock side. Place one 8d nail just above and just below each hinge on the hinge side. It is not necessary to nail through or shim the header jambs. Be careful not to nail through the female portion of the split jamb.

Re-check the operation of the door one last time. Then install the small side (other half) jamb and casing assembly on the opposite side of the door by positioning it so the tongue slips into the groove of the jambs, which have already been installed. Once in place, nail through the casing using 8d finish nails in the same pattern as before. Do not nail through the jamb portion of the casing assembly.

3. Installing casing at Exterior doors:

Using a small combination square, mark a pencil line around the inside face of the door jambs, 3/16" from the edge of the jamb. For the header casing, lay a piece of casing across the top of the opening, marking on it the inner edges of the 45-degree miter. These will fall at the intersection of the pencil lines. Cut both ends of the header casing with these points as the short points of the 45-degree miter cuts. Nail this piece of casing to the head jamb with 4d finish nails in the inner edge of the casing. Repeat for the other side. NOTE: Do not nail in the grooves of the casing as this makes puttying difficult.

Miter the end of a piece of casing so that it matches the piece just installed. Measure and cut from the long side of the miter (the outside) to the finished floor or hold off to allow for underlayment and flooring if not yet installed. This will be the length of that side piece of casing. Hold the side piece in place with the miter joint fitting tightly together. Attach the casing to the jambs using 4d finish nails along the inner edge of the casing.

Nail the outer edges of the casing to the wall using 8d finish nails using the same nailing pattern as was used on the pre-hung doors. It may also be necessary to nail the outside corners of the miter together using 4d finish nails in both directions.

4. Installing Baseboards

Installation of baseboard can be completed only after all pre-hung door units, door casings, underlayment and floor tile, and cabinets are installed. The baseboard should fit snug against the floor tile.

*Measuring
Measuring for baseboard should be done accurately to avoid excessive cutting and waste. Measure, cut and install the baseboard for one room at a time. If there are enough volunteers to have more than one crew working on baseboards, crews can be assigned to different rooms. If using less-skilled volunteers, it’s a good idea to start installing in the largest room.

It is best to install the baseboard by installing the first piece along the longest wall in the room. This piece will be cut straight on both ends to fit the measured distance. The next piece will be installed clockwise from the first piece and will have the left end coped and the right end cut straight. Each subsequent piece will be cut in the same manner as the crew moves around the room. This method eliminates any guess work as to which end of a particular piece of baseboard is to be coped, since all coped cuts will be on the left end of the baseboard material.

On scrap paper, draw a rough plan of the room (including closets) where baseboard is to be installed. Measure each wall surface and record the measurements on the plan, working from left-to-right (the same order in which the baseboard is to be installed.)

Make all measurements approximately 3" above the floor along the wall where the baseboard is to be installed. (From corner to corner or from door casing to corner, etc.) Measure the full length of each section, from the face of the drywall to the face of the drywall (or door casing). For baseboard pieces that will be coped on one end, make sure the measurement is made from above the piece that the coped end adjoins. A common mistake is to measure from the baseboard piece that is already installed, resulting in a piece that is too short once the coping cut is made.

Once all the measurements for a room have been made, two crew members can go to the miter saw and begin cutting the baseboard material. It is a good idea to check the first coped piece for proper fit before cutting additional pieces. Once the crew becomes comfortable with the measurements and the miter saw, cutting multiple pieces ahead of the nailing crew is acceptable.

While the saw crew is cutting the baseboard pieces to fit the room, one or two other crew members can mark the locations of the wall studs carefully on the face of the drywall and place wood or drywall blocks around the room between the floor and the bottom edge of the drywall. The blocks are used to support the back of the baseboard and keep it from turning under. They should be placed at each stud location, on both sides of any corner, and at the edge of any door casings.

When making miter cuts (inside or outside miters) be sure to measure to (and from) the correct end of the angle. This is usually where people make cutting mistakes. If coping the corners, show volunteers how to scribe the profile of the baseboard on the trim. Lap joints should be used if you need to use two pieces of baseboard on a long wall. Break lap joints on studs. Also take care to hold trim firmly (but very carefully!) when using the electric miter saw.

*Nailing
The nailing pattern for baseboard is two 6d finish nails at each stud and at any joints. The nails are spaced approximately ½" from the top and ½" from the bottom of the material. Do not nail in the baseboard's groove or puttying is difficult.

NOTE: When installing a short piece of baseboard (6" or less), it is important to drill the holes for the nails first, or to simply glue the piece in place without nailing, to prevent splitting the wood.

5. Installing Window Sill and Apron
The window sill is fabricated on site from a piece of 1x6 primeboard that may have already been cut to length and routed. The apron consists of a piece of 2¼" door casing trim.

Cut the sill for each window opening 3" longer than the width of the window opening. NOTE: Window openings for the same size window unit vary slightly, so decide on a common overall dimension for all the windows of the same size.

Next, notch the ends of the sill so the edge fits snugly against the window frame and approximately 1½" of each end of the sill extends beyond the edges of the opening. NOTE: The size, depth, and angle of the notch cut will vary from window to window, so each sill will have to be measured and cut separately. A combination square is necessary in determining the depth and angle of the notch cuts as the corners may not be square or uniform in depth. If possible, it is nice to run a router along the exposed edges to ease them. When the sill has been properly cut (no gap greater than 1/8") and fit in place, nail it to the rough-framed sill with 8d finish nails approximately every 12" (liquid nails construction adhesive may also be used in addition to nailing).

The apron fits beneath the stool and covers the gap between bottom of the sill and the top of the drywall opening. Cut a piece of 2¼" door casing, approximately 2" longer than the drywall opening (one inch shorter than the sill). Cut the two ends of the apron on the miter saw at a 22-½ degree angle with the long points of the miter at the thick edge of the casing. Lightly sand the cut ends before installation to smooth and round the edges.

Install the apron with the thick edge against the bottom of the sill. Nail the apron to the wall using 8d finish nails approximately every 12". 6. Installing stairway half-wall cap

The wall cap is fabricated from a 1x8 piece of primeboard. It should be cut to length first, then routed on 3 sides. Line up the wall cap so that it overhangs the edges of the wall equally and attach it to the wall by putting two 8d nails every 10" along the board. Similar to the window sills, an apron should be installed under the wall cap using 2¼" door casing material. The two side apron pieces should be cut to length with one straight edge and one mitered edge while the end apron piece will be mitered at both ends.

7. Installing stairway railing
For each stairway in the home, a stairway railing must be installed. The stairway railing material will be provided as part of the stairway materials kit that should include the stair treads, risers, and railing. Typically, the stairway railing will require three hangers to secure the railing to the stairway wall. One at each end of the railing and one in the middle. To properly set the height of the stairway railing, take a regular carpenter’s square and set the short end of the square against the stairway skirt board. Make a mark at the end of the long end of the square. This mark indicates the height of the bottom side of the stairway railing. In some cases, a decorative wood block will be provided for attaching the railing hangers. Attach the wood blocks or hangers to the wall with the screws provided, adjusting the location to ensure the height of the bottom side of the stairway railing is at the previously marked position.

Next, measure the length of the stairway railing by measuring between the two end hangers and adding approximately 3-4" at both ends for the final measurement of the railing. To add a nice finish to the railing, the railing should be mitered at each end with small return pieces attached to the railing and then attached to the wall. Miter the railing at a 45 degree angle at each end with the miter cut facing towards the wall. Use the railing length measurement as the distance between the two outside edges of the miter cuts. Attach the railing to the hangers using the screws provided. Cut two small pieces of stairway railing to provide the return pieces. One end of the piece will have a 45 degree miter cut while the other end will have a straight cut. Measure the distance from the wall to the outside edge of the railing for the length of the return pieces (each piece may be different, so measure both). Attach the return pieces to the railing with construction adhesive and with a 6d finish nail at the miter joint.

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  Page last updated Saturday, May 3, 2008 at 6:40:13 PM