It is on an order of magnitude, more complicated than installing a new baseboard. Try installing baseboard first, it is good for measuring simple angles and perfecting carpentry skills. To install baseboard, you need a simple mitre saw as you only need to half the angle of the corner and be sure your length is correct to get a good fit; but…..as my old woodshop teacher Mr. Dickson used to say, “measure it twice….cut it once”.
The reason finely installed crown trim is more difficult is that you are dealing with two angles on the cut. Wall/ceiling and wall/wall junctions are never quite exactly 90 degrees and if cuts are off 1/2 degree on a 6″ molding, you will not believe how big the resulting gaps can get! But properly installed, a crown will add a visual interest and value to your room.
If you are going to paint your new crown, you have basically two choices, real wood and a composite product with the generic term MDF (Medium Density Fiberboard).
When it comes to install crown molding, it is really important to fit the proportions of your room and existing trim that will remain. Local suppliers that specialize in architectural millwork can provide you with various samples from which you can choose. In some cases, the local suppliers are more like to suggest moldings that are authentic to your home’s period and regional style. Important to get a good length to see how it looks in proportion to room size and ceiling height before buying all your materials. Proportion is everything!
To insure a good solid installation, I do not trust that all my fasteners will hit wood framing and so I install a 1×3 pine strip around the perimeter of the room a few inches below the ceiling attached to the wall and fastened into the underlying studs….with this in place I can attach the crown without having to carefully measure to insure I am hitting a stud every time with the nail. An air compressor and finish nail gun will greatly speed up installation. You can rent these at the local home store. Have small, flat blade pry bars or stiff putty knives to adjust the trim as you fasten to shift the molding around imperfect “wavy” walls and ceilings. When caulking the inevitable gaps and seams, use a top line elastomeric caulk and have a bucket of water and a wet rag to keep you finger clean and wet as you smooth the caulk. To fill the nail holes, I recommend 3M Patch and Prime as it does not shrink; but do not forget to sand smooth before finishing. Another trick is to pre paint the molding before installing. Let me know if you have any questions…I would be happy to help you.
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