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August 2008
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Flue Tile Planters

Flue tile is not one of those items most home owners will encounter. But they make snazzy planters. They come in lots of sizes,


Installing pre hung doors.

Pre hung doors. Jambs, door, and casing in one convenient package. Pre mortised, for the hinges, pre drilled for knobs and locks, complete with trim, they can be a great time saver for anybody who needs doors.  They are also one of the more difficult things to install correctly.

Rough Opening Anatomy
A typical wood frame rough opening looks like this.


The header bears the weight of the walls and roof and transfers it
to the trimmer and  king stud. The trimmer holds the end of the header,
and the king stud holds the trimmer in place.

Tip: When building door and window openings, select the clearest lumber
you can. Not having to nail or screw through knots is worth a lot. Also
nail or screw the trimmers and king studs from both sides, into each
other. The same for the header.

When replacing a door in an existing wall, hope for the best.

Rough Opening Calculations
Typically a rough opening is sized 2'' wider than the door width and 2 3/4'' taller than the door height. Example: Door size: 3' 0" x 6'8" Rough Opening: 38" x 82 3/4"
This gives you room to move to cover variations in plumb, level and square. Mike Merisko has a concise guide here. These calculations are generous, and can be made smaller depending on how well the original framing was done. The less shimming you have to do the better.

Checking the opening.
You need to get your level out and check the frame for plumb, so when you install the door it is plumb and will work correctly. I wrote about this here. The header for level and the floor. The floor is important as you will probably need to either shorten or shim up one jamb or the other depending on how it runs. The height of the gap of the bottom of the door is important depending upon what you are doing for flooring.

Squaring the frame

Your door has come from the factory with a plastic widgit through the lock hole and the frame to keep the door from swinging out of the frame for shipping. There is also a strip of wood or a threshold attached to the bottom of the door. Before you remove them we want to add some strips to the door to keep it in place before we install it.

We need a couple of measurements. Check that the gap is equal between the door and the frame. On the hinge side of the door, we want the measurement across the outside of the frame. We will need a couple of pieces of 1/2'' plywood about 4'' wide, cut an 1/8'' smaller than the width of the frame. The 1/8'' allows you to leave a small reveal on both sides, so the door will slide into your opening. One goes on the top of the door frame, with two screws on either jamb and one into the head jamb. The other one goes below the bottom hinge but above the floor. Check your gaps before attaching them. The more care you take here the less swearing you may do later:)

On the other side we need the inside dimension between the jambs. What we will do is cut a couple of 2×4's to the inside number. Cut a couple of 1/2'' plywood strips to the outside dimension. Center and attach the 2×4's to the plywood strips. The 2×4's are acting as stretchers to keep the door square. Attach the plywood/2×4 stretcher to the door frame with 1 – 1 1/4'' inch screws.

Do Not screw through the frame sideways into the 2×4!! They are spacers and are attached to the plywood. Once you attach the door you will not get those screws out. You will end up buying another door and doing it all over. Your friends will laugh, and the noisy neighbor will call the police if you try to remove the body of the door wrapped in carpet. They will laugh too.

Inside Details

This door is going between an existing wall into the new space. The bit of plywood on the left is attached to guide the frame to be level with the drywall, minimizing caulking or  other trim work.

Prefit the door and check the top gap across the door and frame. This is where you check to see if you need to cut the bottom of the door frame because your floor is not level. 

Cut or shim the legs as required, reset the door and begin attachment. Center the door in the opening, Shim as necessary and begin.

Be careful that you are allowing enough room at the bottom of the door to allow it to open and close over what your floor covering will be.

Shims are small pieces of wood with a triangular cross section. You use them in pairs. the point is to have a flat surface to attach your fasteners through. They can be offset if your trimmers are twisted. Take care when doing this however.

Whenever I install pre hung doors, I like to attach them with screws rather than nails. You can make micro adjustments with a screwdriver.  I always attach the hinge side first. Drag out your level and check the door frame is plumb before attaching it to your framing. I attach it just above the hinge on the bottom, above the middle hinge or center depending on how many hinges, and just below the bottom hinge.

Next I attach the lock side, at the bottom, just above the lock plate, and below the upper inside corner. Now the door will not fall down or twist in the frame when you undo the plywood from the hinge side. 

Moving to the hinge side, remove the plywood, and open the door just a little bit, to check the swing. If you have shimmed properly the door will stop where you let it go and will not try to open or close. This is Plumb.  Check that your gaps on the  hinge and lock side are correct and equal. This is square.

You can now finish the attachment, make any final adjustments and move to the next project. 

The small holes will easily be puttied or covered by the trim depending on your attachment.

You now have a solid door assembly that is much easier to move into position and to square up.

It sounds like a lot of work, but it really isn't.