Shaving poured rough entry for door


  #1  
Old 07-21-19, 06:37 AM
R
Member
Thread Starter
Join Date: Jan 2019
Posts: 60
Upvotes: 0
Received 0 Upvotes on 0 Posts
Shaving poured rough entry for door

I have a poured 8" thick concrete foundation in basement that I need to replace an entry door.

I would like to use a prehung door but the height of the entry is approx 81 3/4". The door I was looking at needs 81 3/4" so im guessing it will be tight. I dont want to special order a smaller door or get into cutting standard door down.

What would be the easiest method to shave down that small amount from the concrete?

I planned to install 2x buck on the sides for the door to attach to. Is there any issue not having 2x on top of the door? I never installed a prehung door before but I am assuming it doesnt get attached at the top anyway.

Thank you.
 
  #2  
Old 07-21-19, 06:39 AM
P
Group Moderator
Join Date: Mar 2003
Location: NC, USA
Posts: 27,759
Received 2,181 Upvotes on 1,951 Posts
I don't think it hurts not having a 2x4 across the top except I don't like having the untreated frame of the door close to masonry without some barrier in between.
 
  #3  
Old 07-21-19, 07:40 AM
R
Member
Thread Starter
Join Date: Jan 2019
Posts: 60
Upvotes: 0
Received 0 Upvotes on 0 Posts
Great point that I didnt consider. Perhaps flashing tape or something.

Is it feasible I could grind a 1/4" or 1/2" of concrete?
Does a prehung door typically get screwed to header?
 
  #4  
Old 07-21-19, 07:51 AM
H
Member
Join Date: Nov 2012
Location: USA
Posts: 2,316
Received 296 Upvotes on 254 Posts
I'd be careful about shaving down the concrete, you don't want to create a low spot for water to pool and then rot the door.
That being said, a simple circular saw with a masonry cutting blade will allow you to "score" lines in the concrete, then score lines 90' to that, then finish with a chisel.
(It's basically the same as scratching a diamond pattern into the ice on a car windshield so that it scrapes off easier.)

Make sure the stairwell down to the door has a drain, otherwise you'll get water building up.
 
  #5  
Old 07-21-19, 09:46 AM
R
Member
Thread Starter
Join Date: Jan 2019
Posts: 60
Upvotes: 0
Received 0 Upvotes on 0 Posts
Hal, Im going to shave from the top if its feasible.

So I am about a 1/2" away from standard 160 dollar door from the hardware store vs. custom order 78" door at about 400+ dollars.
 
  #6  
Old 07-21-19, 01:00 PM
P
Group Moderator
Join Date: Mar 2003
Location: NC, USA
Posts: 27,759
Received 2,181 Upvotes on 1,951 Posts
With a diamond blade in a circular saw and a cartridge respirator to survive the dust you can make the cut.
 
  #7  
Old 07-21-19, 01:15 PM
Marq1's Avatar
Member
Join Date: Sep 2016
Location: USA MI
Posts: 9,745
Received 1,210 Upvotes on 1,098 Posts
So the obvious question, what's at the top of the door frame, wood?

Much easier to trim than the concrete!!
 
  #8  
Old 07-26-19, 12:49 PM
R
Member
Thread Starter
Join Date: Jan 2019
Posts: 60
Upvotes: 0
Received 0 Upvotes on 0 Posts
what should I use as a barrier between concrete and the prehung door jamb? Like a flashing tape? What I saw online for "flashing tape" was kind of expensive for a whole roll... I would only need enough to cover the top portion of the jamb.
 
  #9  
Old 07-26-19, 02:17 PM
P
Group Moderator
Join Date: Mar 2003
Location: NC, USA
Posts: 27,759
Received 2,181 Upvotes on 1,951 Posts
Flashing tape would be the best as that's what it's designed to do. There are also butyl tapes that might be good, perhaps one with an aluminum facing though I don't know how the price compares to flashing tape. My third pick would be a couple layers of tar paper, sheet vinyl or some other material very resistant to letting moisture pass through.
 
  #10  
Old 07-26-19, 03:59 PM
R
Member
Thread Starter
Join Date: Jan 2019
Posts: 60
Upvotes: 0
Received 0 Upvotes on 0 Posts
Does the flashing tape get applied to the wood jamb or the concrete?
 
  #11  
Old 07-27-19, 03:53 AM
P
Group Moderator
Join Date: Mar 2003
Location: NC, USA
Posts: 27,759
Received 2,181 Upvotes on 1,951 Posts
Read the instructions for the product you choose. Normally it's applied to the rough opening but I think that's primarily for the ease of construction so you can apply the tape then just set the door in place on it. If you put the tape on the bottom of the door then you need to be careful to not drag the door across the floor or set it on anything that might damage the tape.
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description: