Door jamb questions???

[Alan in Little Washington]

No work done on the shop door yet today but just picked up the laminated safety glass. Its time to start thinking about the jamb.

A couple of questions for you guys that have made/make your own jambs (if there is anyone who does this in this day and age of prehung doors ):

1. I will be using oak (more of my almost free oak) for the jambs. Should I mill it to a standard 3/4", make it thicker- 1", or what? The oak is 5/4 rough cut. I think my rough-in will allow up to 1 1/8" thick jambs. I plan to nail and maybe screw the jamb to the framing. At least one long hinge screws will be long enough that goes into the framing also.

2. Most of the manufactued jambs I've seen, I think even the finger jointed ones, have dadoes (stress relief grooves?) cut lenthwise in the back face the jamb. Do I really need to do that?

3. Are ball bearing hinges worth the additional expense? I thought I might need them since the door is so heavy.

Thanks.

 

[BobN]

Alan,
I've made a few jams and I have always used 3/4". However if your rough in allows it and the door is as heavy as you say, you may want to go thicker than 3/4" to give more wood for the hinge screws to bite into.

I have never put the dadoes (stress relief grooves?) in the jam. Some of mine have been in place for 10 years or longer with no problems.

I have never used the ball bearing hinges, however I do go to 3 or 4 hinges on a heavy door. And I generally buy and used screws longer than what comes with the hinges.

Bob

 

[walnutjerry]

No work done on the shop door yet today but just picked up the laminated safety glass. Its time to start thinking about the jamb.

A couple of questions for you guys that have made/make your own jambs (if there is anyone who does this in this day and age of prehung doors ):

1. I will be using oak (more of my almost free oak) for the jambs. Should I mill it to a standard 3/4", make it thicker- 1", or what? The oak is 5/4 rough cut. I think my rough-in will allow up to 1 1/8" thick jambs. I plan to nail and maybe screw the jamb to the framing. At least one long hinge screws will be long enough that goes into the framing also.

2. Most of the manufactued jambs I've seen, I think even the finger jointed ones, have dadoes (stress relief grooves?) cut lenthwise in the back face the jamb. Do I really need to do that?

3. Are ball bearing hinges worth the additional expense? I thought I might need them since the door is so heavy.

Thanks.

Alan------when I worked for the millwork co. we always made door frames 7/8" -1 1/16. The thicker you can make them the better they hold screws and carry the weight of the door. The relief cuts in the back are to help relieve the tendency to cup, especially in wide frame stock. If you have wide flat sawn oak (anything over 5 1/2") I would reccomend to do that. We also dadoed the top of the jambs about 1/2" down from the top to the top of the dado to receive the header, usually 3/8-1/2" deep, and wide enough to accept the thickness of the frame material.

Clear as mud, huh? Hope this is of some help to you.

Jerry

Sorry I cant attest to the ball bearing hinges. I would recommend 3 hinges for the door.

 

[Alan in Little Washington]

Alan------when I worked for the millwork co. we always made door frames 7/8" -1 1/16. The thicker you can make them the better they hold screws and carry the weight of the door. The relief cuts in the back are to help relieve the tendency to cup, especially in wide frame stock. If you have wide flat sawn oak (anything over 5 1/2") I would reccomend to do that. We also dadoed the top of the jambs about 1/2" down from the top to the top of the dado to receive the header, usually 3/8-1/2" deep, and wide enough to accept the thickness of the frame material.

Clear as mud, huh? Hope this is of some help to you.

Jerry

Sorry I cant attest to the ball bearing hinges. I would recommend 3 hinges for the door.

Thanks, I think I will remeasure and check the plumb of the rough-in, then go with as thick a jamb as the opening and my 5/4 stock will allow; and also make the relief cuts. At another's suggestion I'll also replace one screw in each hinge with a long one (3") that goes through the jamb into the rough framing.

 

[Ozzie-x]

One additional tidbit, the back side of the jambs can remain rough sawed since they don't show. This might help in making the jamb thicker, I would leave them as thick as possible.

 

[Joe Scharle]

Alan, that door is as heavy as any exterior door (I've seen it) and I'd hang it as such. 4 - 4 hole hinges. Some of the lumber in your stack is flatsawn. If you use it for the jam, remember the I.D.I.O.T. axiom for drawers, to prevent cupping at the face trim.

 

[Ray Martin]

Alan,

Sounds as if you've gotten some good advice in this thread. You did mention checking the plumb of the framing... I tend to be a bit fussy about that. I like to make sure the trimmer studs are VERY square and plumb and have no structural defects (big / loose knots, cracks, twists, etc). If the opening is not square and plumb, the door might move by itself when partly open... or not have an even spacing all the way around.

Assume that the door will be there long after you are gone. Sign and date the trimmer stud :lol:

Ray

 

[Mark Anderson]

i'll put in a plug for the ball bearing hinges, they do make a difrance with a heavy door... and it's your house.

in planing the jamb thicknes mke sure you leave a bit fo room for shims around the door. 1/4 inch all the way around comes in handy. on a heavy door i would use two longe screws on the op hinge and one on the bottom. and some long screws on the strike plate wouldn't hurt, sooner or latter someone is gong to slam that door, and it will be like a sledge hammer hitting that side jamb.

one note, make sure those shims are made out of dry stock, if they shrink up after installation they are useless.