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What to do with gap in bottom of crown molding?

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Dec 04, 2013, 02:08 AM
What to do with gap in bottom of crown molding?
This is not crown molding going into a wall. I use molding to make a fireplace shelf. The photo below is the top left of my fireplace mantel. There is about 1/2" gap between the molding and the wood column. I didn't want to take it off because I already nail and glue everything. The reason there is a gap is because the surface behind it was not even (got mortar on it).

So what to do to cover this gap? I was thinking:
1. Use drywall mud to cover it. It's far enough so there is no heat up there. But would mud crack badly over time?

2. Use bondo to fill it. This material is hard and no crack. But even so I don't know if it's ugly or not.

3. Use some kind of trim. Any suggestion from Home Depot or Lowes?

Dec 04, 2013, 07:46 AM
Can you back up and take another picture please so we can see the whole thing?
If you want this to look right and be safe your going to have back up and make some changes.
#1 There can be no wood used within 8" on the sides and 12" over the top of a fireplace.
#2 It looks like your planning on painting that trim, by not using a better grade of pine that was knot free your making your job to finish far harder.
#3 The trim should have bee assembled using A Kreg tool on the back side so it would not be twisted and a there would not be a huge gap like that.
#4 I would have primed and painted one coat before installing. Just makes it a whole lot easier to paint.
#5 Trying to putty, fill all over the face of that to make up for lack of proper prep work is just not ever going to look right.

Dec 04, 2013, 12:53 PM
Pic #1 below show my whole fireplace now.

Pic #2 is the layout I found from the internet. I copied this layout. They use crown molding around the fireplace, no 6" side or 12" top. My fireplace is very deep inside. I wonder if it's OK if I only turn it on like 1-2 a year

Pic #3 is also from internet and I tried to copy how they lay the wood. They do have some tile space on top.

So what do I do now? Obviously I am amateur. I would hate to pull everything out now Frown

Dec 04, 2013, 03:02 PM
Since it looks like the crown is not installed yet based on your first picture, I would put in a piece of 1x behind the crown and over the existing 1x3 around your fireplace. This piece will be nice and flat for your crown. Then I would use a piece of cove molding that is very flexible to cover the gap between the new piece of 1x and the existing 1x. Then if there is a slight gap I'd probably use caulking to fill in the now much smaller, more manageable gap.

General Disclaimer

Any advice given here is general in nature and is not necessarily valid for your given area. If in doubt check with your local codes enforcement department for what is required when doing electrical, plumbing or structural work on your house. Permits may or may not be required in your area and home owners may not be able to DIY some tasks. I have no way of knowing if you have the skills needed to complete the tasks you are asking about, when in doubt seek professional assistance.

My advice may be worth exactly what you pay me for it. :-) For the record I did not stay in a Holiday Inn Express last night.
Dec 04, 2013, 03:05 PM
Bondo is polystyrene plastic, that burns like gasoline, so you can't use it as filler. best bet would probably be Durham cold water putty.

it will look like a patch-up because it will expand and contract at different rates than the plaster.

best course would have been to test-fit before securing the mantel material and fiddle the trim to fit.

the absolute no-fooling best course from the planning stage would have been to cement-board along the restricted zone for flammables, and use tile or a stone product secured with mortar within that safety zone. then put the wood up outside that region.

I hate to say "take it down, take it all down," not the least reason being it could be copyright violation Wink but...

sig: if this is a new economy, how come they still want my old-fashioned money?
Dec 04, 2013, 03:50 PM
It's not copyrighted and I will not take you to court as long as you agree with me. Smile

Dec 04, 2013, 04:14 PM
Thanks for the advice above folks.

My question is: how is the flammable zone being measured? Is it from the edge of the fireplace door? Or from the brick opening?

The reason is that inside that black fireplace door was at least 5" brick top/bottom and 10" brick left/right. My old fireplace was too wide so I put some bricks on left/right, effectively making it narrower to fit that door.
Dec 04, 2013, 07:44 PM
OK, I'll be the stick-in-the-mud and say it: Tear it all out and start over again!

Now that you hate me just a little, here's the deal - A Joe already mentioned, you have combustible material too close to your firebox. You can get away with being this close if you have non-combustible material like stone or tile but not wood. As measured from the inside edge of the firebox you need a minimum of 8" on the sides and 12" across the top.

I know, I know, you found some other pictures on the internet. I know I can't be the first to say that just because it's on the internet doesn't mean that it's true, or right.

The simple facts are that your wood is too close to the firebox. It's a real fire hazard. If your house does burn, there is an excellent chance that your insurance will not cover it - if there is enough left for them to figure out that the fire was caused by an out of code trim package.

So save your house and maybe your life and start over again with any wood spaced further from the box. And while you are at it, spring for a better grade of material than common pine - it will sand out and pint up much nicer.

Dec 04, 2013, 08:27 PM
There should be installation instructions with the unit you are installing, or you can probably get them off the internet. On units like that, the installation instructions is the first place to start, it will give you clearance numbers to combustibles and help you to install it correctly. Wood stoves, pellet, or either gas type all have their own figures for clearance to combustibles and the required size of exhaust pipes

They make it look so easy on tv, don't they
Dec 04, 2013, 09:26 PM
Thank you. I think it's clear now I have to rip out everything :'( (crying).

@Re-mdlr I only bought the fireplace door and put on existing masonry brick fireplace. I added in the mantel myself. So there is no installation guide for the mantel :P
Dec 05, 2013, 06:46 AM
If your going to remove, spend some more time looking over some of some of the stock picture on Google when you key word "fireplace surround".
Most are just stock moulding material off the shelf in any box store.
Just using 1 X 4 pine was not the best look.
Just because it's your first time doing something like this does not mean it has to look that way.
That's one item that anyone walking into that room is going to see so it needs to look nice.

Dec 05, 2013, 04:01 PM
@joecaption what wood material is good for this? The pine wood I bought was pretty smooth so painting on it won't see any bump or things like that.
Dec 05, 2013, 06:59 PM
All wood comes in different grades.
#1 Being the highest, it cost more but there's no exposed knots in grade 1.
Lowes carry's a clear grade of pine.
Poplar is a another way to go.
For my taste I just would have used 1 X 4's.
And for sure would not have used any wood at the bottom.
Something like this would be simple for anyone to build with stock moulding.

Dec 06, 2013, 11:00 AM
Originally posted by joecaption:
It's not copyrighted and I will not take you to court as long as you agree with me. Smile

Joe, I was thinking of one Mike Holmes...

sig: if this is a new economy, how come they still want my old-fashioned money?