Following the last discussion:
We found a supplier of ready stock fiber enforced plaster crown moulding in Toronto; they sell only $6-$12 per piece (8f Length, 5.5”-7.5” width). It’s cheaper than MDF, wood, polyurethane moulding in market. They have many pattern designs you can choose for.
When you find the right materials, the installation would be much easier. The most challenge for install crown moulding are the uneven ceiling/wall and corners. So, the plaster moulding that comes with the character of easy cutting/trimming/filling make the plaster crown moulding stand out.
Besides the ordinary tools DIY will stock, you just need few special tools: Heavy duty compass or miter gauges, Chalk line, and stub finder. You can rent /buy a 12" Double Bevel Sliding Compound Miter Saw, or build a wooden miter box. Air compressor and brad nailer is also useful.
Supply: Premium Polyurethane Construction Adhesive, ready-mixed joint compound, spackling compound.
That’s all you need.
It’s better to prime and paint the moulding first. Then touch up after the job complete.
The planning procedure need not to be mentioned, we’re discuss the installation itself here.
First, according the dimension of the crown moulding’s projection, chalk/draw a straight line in the ceiling and wall. Then, use a compass (open in the same dimension above) to get the line flush with the wall/ceiling, or cut a small piece (1’ long) to try, dry fit several different points. Now you have some idea where are the uneven in the wall/ceiling.
There’re two ways to deal with it. Trim the moulding; lowering the moulding then fills the gap. Since the plaster moulding is soft enough can be cut/scrape by utility knife, you are better to consider trimming the moulding, unless the different is too great.
After you decide the method, you are getting the guide line (in the wall) accordingly. Now, you put some nails in the guide line, for temporally support purpose.
Second, find some stubs and ceiling beam.
Third, use compass/ miter gauges to check the angle of each corner (inside/outside). The moulding layout position to cut is different if you choose wooden box or 12" Double Bevel Sliding Compound Miter Saw. Better you use the later.
Now, you can start to cut and install.
Remember to dry fit each moulding before put the glue. The moulding will be use Premium Polyurethane Construction Adhesive to attach into the wall/ceiling. (There is other way to glue the plaster moulding into position by using a gypsum adhesive (such as Sheetrock 90), but it’s better for the plaster guy do it in an empty room). The air brad nail or the screw (use screws should go through the pre-drill hole in the moulding) can be help for fastening.
All the joints (flat or corner) can be filling with ready-mixed joint compound. All the gaps (in wall/ceiling) and nail/screw holes can be filling with spackling compound.
Finally, you got to touch up or prime/paint the moulding once it dries completely.
Now, you can are amazing how wondeful your room been transformed.