# Interior shiplap inside and outside corner finishing



## Steeters

Issue: Looking for advice on how to finish interior shiplap inside and outside corners so that they look good and will be "easy" to get right for someone who is handy, but not a professional.

Background: new gas fireplace, new construction, would like to build fireplace surround. Fireplace is to code, inspected, etc. The fireplace is direct vent that is encased in a 72" wide and 24" deep false fireplace that goes from floor to ceiling. The fireplace itself is 24" off of the floor.

My intent is to install slate from the floor to about 48" and then shiplap the front and sides of the fireplace to the ceiling. I'd rather not use trim pieces on the outside as I think it has a better look when you don't.

Those outside corners need to be so perfect to look right that I would like some advice on how to improve my chances of success. I can't see any photos online well enough to see how they are joining the outside corners...I assume 45s, but not certain. I think I can bury the inside corners in a piece of quarter round (if I must) where they meet the wall...unless you have other suggestions. 

I have a table saw, miter saw, basic measuring tools, air tools, etc.

Suggestions? Thanks!

Steve


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## Black540i

Personally I would do a 1x1 square from floor to ceiling for the inside corners and probably 2 - 1x2's mitered together for outside corners.


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## Ghidrah

We call it clapboard up here, If you aren't going to apply C. boards and ground strips there are clapboard corner caps or shields. Otherwise the corners are treated the same way as lacing cedar shingles at corners. "Always start on the side you just finished" this will ensure you cross back and forth creating a watertight barrier.


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## Steeters

Good suggestions. I was going to try and get that "architectural" look with no trim pieces if I can avoid it. 

Wondering if I just used a jig to cut the fronts and the sides to consistent dimensions. And then install them, with hidden shims where necessary, with the idea that I'll make a bunch of perfect right angles and basically ignore the squareness of the chimney and walls...it is only a facade anyway because it is interior trim.

Suggestions?


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## Ghidrah

Won't work, the clap is tapered bottoms are thickerer than the tops and sit on the course below. Be aware, red and or white cedar clap is very brittle, one of the reason why most use caps or C boards. If you have pine you might get away shaving the corners but I'd predrill the ends and use 4 or 5p box nails. Finish nails will probably pull through the boards from swelling and contraction in a few yrs of heat and humidity


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## Helicon1

Are you sure you want a shiplap wall? Or just a regular plank wall with s4s lumber. You say you have a table saw so you could do 1x4 or 1x6 clear pine, cut a dado into one length of each board to give you the reveal you see in the picture you posted. That way your inside/outside corners are far easier for either butt joints or MITRE's...


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