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#### cvcman

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building a deer blind,,,it will be 55" square with 5ft high walls...I want the inside height at peak to be about 7ft...is there an easy way to figure the angle cut at the peak ??

I have a speed square but not a framing square...

thx guys

#### TimPa

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rise is 84" - 55" = 29"
run is 55" - 1.5" (ridge board, adjust as req'd) /2 = 26 3/4"

peak angle is 47.3 deg. this assumes the rafter will sit on outside of wall (no birds mouth). otherwise you need to provide more info.

#### cvcman

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rise is 84" - 55" = 29"
run is 55" - 1.5" (ridge board, adjust as req'd) /2 = 26 3/4"

peak angle is 47.3 deg. this assumes the rafter will sit on outside of wall (no birds mouth). otherwise you need to provide more info.

Wow, thx for the quick answer....I wont have a ridge board, will use plywood gussets,,,,,,will this chg the angle ?

Also no birds mouth,,,,will sit on top of outside walls...I assume I can get this angle with a speed square ???

Thx so much !!

#### joecaption

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Why only 5' walls?
Going to have a bunch of waste that way, and going to have to walk around bent over.

#### cvcman

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Why only 5' walls?
Going to have a bunch of waste that way, and going to have to walk around bent over.
I will be sitting,,,and shooting windows will be 3ft above floor so waste will be zero

#### joed

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45 degree angle will make inside height half the width. Don't forget to add the thickness of the rafter to get the true outside height.

#### cvcman

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45 degree angle will make inside height half the width. Don't forget to add the thickness of the rafter to get the true outside height.
Im lost now,,,,so the inside height will be half the width of the building ??? The width is 55" so the inside height will be 27-1/2" high ???

All I want is an inside height of 7ft at the peak,,,5ft high walls,,,,55" sq building

#### cvcman

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rise is 84" - 55" = 29"
run is 55" - 1.5" (ridge board, adjust as req'd) /2 = 26 3/4"

peak angle is 47.3 deg. this assumes the rafter will sit on outside of wall (no birds mouth). otherwise you need to provide more info.
isn't the run the width of the bldg. ??? That is 55"
and isn't the rise the height of the walls ? That would be 60" not 55: as you put above...not being a wise guy but im kinda lost....thx

#### joed

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Im lost now,,,,so the inside height will be half the width of the building ??? The width is 55" so the inside height will be 27-1/2" high ???

All I want is an inside height of 7ft at the peak,,,5ft high walls,,,,55" sq building
The inside height to the peak of the roof will be half the width plus the height of the wall.
If you want 7 feet(84") at the peek and your walls are 5 feet(60") then your roof needs to be 24" taller than the wall. If you cut the rafters at 45º then it will be 27.5" taller than the wall or 7feet 3.5 inches.
This also assumes that the 55" is to the outside of the wall since that is where the rafter will sit.

#### Mingledtrash

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isn't the run the width of the bldg. ??? That is 55"
and isn't the rise the height of the walls ? That would be 60" not 55: as you put above...not being a wise guy but im kinda lost....thx
I think it would be great if you could clear up what type of roof your doing.
everyone here from what i can tell is giving you the rise for a gable roof. most dear blinds i have seen have a single slope or shed roof so maybe this is causing some confusion

#### cvcman

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The inside height to the peak of the roof will be half the width plus the height of the wall.
If you want 7 feet(84") at the peek and your walls are 5 feet(60") then your roof needs to be 24" taller than the wall. If you cut the rafters at 45º then it will be 27.5" taller than the wall or 7feet 3.5 inches.
This also assumes that the 55" is to the outside of the wall since that is where the rafter will sit.
So then the 46.5 or 47 would give me close to ft...and it IS a gable roof....

#### joed

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Maybe this will explain it.
The height of the roof is A +B.
B=C if it is a 45º angle on the roof.
C is half of D.

Shorten B and the 45 angle gets larger. The new angle for a 24" rise of B is 41.1º.
The original calcs were wrong as they used 55" wall height instead of 60"

#### SeniorSitizen

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building a deer blind,,,it will be 55" square with 5ft high walls...I want the inside height at peak to be about 7ft...is there an easy way to figure the angle cut at the peak ??

I have a speed square but not a framing square...

thx guys
Let's forget about the angle and just do it.

Lay a 2x4 across the top plates wall to wall. Find and draw a line on the center line of the floor. Stand a 2x4 on the floor, edge on the center line on the floor. Plumb that 2x4 vertical and tack to the 2x4 that's laying across the top of the walls. Tack the bottom to the floor.

Measure up the 7 ft. or whatever you want and put a mark on the vertical 2x4. Lay 2x4 rafter, extra long from the top plate beyond the 7 ft. mark on the vertical 2x4. Scribe a line on the rafter for the plumb cut using the vertical 2x4 edge as the reference. Lay a straight edge on top of the top plate beside the proposed rafter and scribe a line. That will be the seat cut. If you want a birds mouth draw it just after the seat cut mark. There, you be done and we don't need worry our pea picken brains about the angle.

#### TheDeckBarn.com

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why not just cut 2 rafters, 5/12, 6/12 whatever you prefer. put one on 1 side 1 on the other. find the center where the 2 meet, scribe and repeat

#### BigJim

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55 inches wide will be the span, not the run, the run is half the span.

#### TimPa

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2 mistakes in my first post, duh.

rise is 84" - 60" = 24"
run is 55" /2 = 27.5"

rafter cuts will be 41.1 degrees on the wall end, sitting on a (horizontal) top sill, flush with outside wall, and 48.9 degrees at the peak end.

#### cvcman

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2 mistakes in my first post, duh.

rise is 84" - 60" = 24"
run is 55" /2 = 27.5"

rafter cuts will be 41.1 degrees on the wall end, sitting on a (horizontal) top sill, flush with outside wall, and 48.9 degrees at the peak end.
so.....if I cut the ridge angle at 48.9 or 49 ...that will give me about 7ft to the peak from the floor with the other end sitting on top of the 5ft outside walls, correct ??

Now the 41.1 deg cut on the other end is so the fashia board will be nailed on the rafter ends square correct ?

One more ? on the roof...im going to use drip edge and felt and shingles...does the drip go on first at the eves and OVER the felt on the rake ???

Do I need to seal or run a bead of tar up the rake before putting shingles down ??

Thx a lot guys !!

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