Directions to determine barn door sizes
Swinging Doors
Swinging doors can be hung either inside the door opening (this allows the doors to swing both in and out unless a stop is put in place) or hinged outside to cover the opening by 2 or more inches (thus only allowing the door to open out).The size and weight of the door determine the quantity and strength of the hinges necessary. We do not supply door hinges.
Swinging doors that close inside the rough opening:
To determine the exact door size necessary, allowance for jamb clearance may be needed.
If you already have a jamb, the door should be ¼" to ½" smaller than the inside of the jamb. This will allow for swelling and damp weather. If the hinges are installed barn style (flat against the door and the wall) a jamb might be unnecessary. You might only need an inside trim board to close the gap next to the wall.
To determine the size of a swinging door closing inside the wall, determine the rough opening width. Subtract the combined thickness of the side jamb you plan to use (if any) and an additional 1/2" for clearance and swelling. That is the exact door width needed. Subtract the top jamb thickness and the bottom sill thickness from the rough opening and allow ¼" top and ¼" bottom for clearance and swelling. Allow an additional 3/8" for center clearance when installing split pairs.
Example. With a 98" rough opening height, allow ¾" for the top jamb (if any) and ¾" for the bottom sill (if any). Note: even if you do not use a bottom sill, allow 3/4" to prevent pebbles from stopping door movement. Allow ¼ top and bottom for swelling. Example: 98" - (¾ + ¾ + ¼ + ¼) = 96" exact door height.
Swinging doors that close outside the rough opening:
For uneven or irregular openings, or to maximize opening space, swinging doors sometimes overlap the rough openings. A 2" overlap on each side and at the top will usually suffice. Hence, a rough opening 48" wide x 89" high will need 48" + 2" + 2" = 52" in width and 89 + 2 - 1 (clearance for pebbles) = 90" in height.
Dutch Paddock Doors
Dutch style swinging doors often are set to overlap the openings. It is common to allow 2" at each side (accordingly an overlapping Dutch door for a 48" wide opening would be 52" wide) and 2" at the top of overlapping style Dutch doors. The door bottoms are usually 1" above the floor, except when used as paddock doors for horses. For Dutch paddock doors, builders often use a pressure treated sill at the bottom. This raises the bottom off the floor approximately 6" so that it doesn't bump into road apples or built up ice, snow, or sawdust. Some horse owners do not like this sill because it interferes with free passage of the wheel barrow. This paddock door bottom sill issue also applies to paddock doors that are not overlapping, but are set inside the doorway (accordingly a 94" opening height for a paddock door overlapping 2" at the top and 2" onto a 6" sill at the bottom would require a 90" paddock door). Verify that the swinging doors have room to completely open without roof or sidewall obstruction before hanging.
Horse owners are often reluctant to use Dutch style paddock doors because they don't stay aligned as you open them. If your Dutch paddock doors pinch your fingers or gap open excessively when the doors are opened straight away from the wall, the reason is that the hinge pins aren't in line. If you were to look straight down through the hole of the top hinge pin to the hole of the bottom hinge pin, all the openings should be a straight line. If they aren't, shim or adjust them and your doors will stay aligned as you open them.
Sliding Doors
Larger sliding doors (10' wide, 12' wide)
The top of the mounting brackets of the tracks we use are approximately 5 1/2 " above the top of the sliding door. If there is sufficient clearance for the track and trolleys, the door height can be set to overlap or match the top of the opening (the track cover hides the track).The sides of 10 and 12 wide sliding doors usually overlap 3" at each side. Accordingly, a pole barn with the posts set 12' center to center would use a 12' wide door, covering each post 3" and leaving an 11'6" inside opening. With an overall rough opening height of 10' floor to header, we would make our doors 1" less in height to clear the pebbles. For clearance and aesthetic reasons, the door height can be shortened and the opening at the top covered by a valance inside the door (can be rounded) and a track cover outside the door. Note, sliding door trolleys usually have a dog leg in the vertical bolt which, when twisted, allows the door to be moved against or away from the wall. When using battens or brick, be sure to furr the track out accordingly to allow the door to clear the battens as the door is sliding open. A rub rail is places along the bottom of the wall to hold the door away from the wall and battens. Make the rub rail ½" thicker for a little extra clearance.
Smaller Sliding Doors
For smaller sliding doors (stall doors or carriage house doors) 4' to 8' wide, the overlap is usually 2" on each side. A 52" wide door covers a 48" opening nicely. Leave a 1" gap under the door for pebble clearance, as well as clearance for the stay roller at the door bottom. Make sure there is a clear path for the door to slide into. An 8' track will work on a 52" wide door if the leading edge of the trolley roller is 3" away from the door sides.