House framer/builders, Roof question(s)

[drajj5]

So my wife and I are toying with a remodel of our home. Our House is a simple 24x40, 2 bed 1 bath. We agree that we need a second bathroom and would like to add a garage to the footprint of the house. this addition will create some interesting roof lines as the house will (not) have equal dimensions.... The question that I pose, is "probably simple" but I cannot work it out in my head the truss dimensions. I am attaching a pic of the new plan and for those who can help please do!

Old house
24x40 - 4:12 pitch 24' Truss - (simple truss - load bearing through the center).

New house
uses the 24x40 footprint with the addition of the garage and an 8' bump-out....

We would like to vault the ceiling and have a much steeper pitch, 8:12 - (scissor truss - 24') open span across the original footprint. With the garage being 24' deep possibly doing the same. However - The 8' bump to allot the addition of the second bath is messing up my roof-line/valley.

Thanks

 

[CliffordK]

Are you replacing the entire roof?

I wouldn't choose a flat valley. It sounds like a problem waiting to happen.

You can get around that issue in two ways.

#1, rotate the garage roof 90 degrees so it meets the main roof at a right angle. Then it will create a sloped valley.

#2, rotate the entire roof 90 degrees so that the garage roof is at the same angle as the main roof. Then you could deal with the peak of the garage in a couple of ways, from either having a tall back wall, and the peak near the peak of the main house, or a peak in the middle and a shorter roof than the main house.

#3, raise the whole roof so that the peak will be near the wall between the garage and the main house. Your dimensions are not symmetrical. However, the slope on both sides doesn't have to be the same.

There are a few different ways to achieve a vaulted ceiling in the living room. One method is to use rafters hanging off of a center support wall. You don't seem to have that (although the side wall of house which will now between the garage and the house could be made into a supporting wall.

You could also put in a center support beam and rafters.

There are also some truss designs that will give the effect of a sloping ceiling, that won't be full height on the inside.

 

[drajj5]

Are you replacing the entire roof?

I wouldn't choose a flat valley. It sounds like a problem waiting to happen.

You can get around that issue in two ways.

#1, rotate the garage roof 90 degrees so it meets the main roof at a right angle. Then it will create a sloped valley.

#2, rotate the entire roof 90 degrees so that the garage roof is at the same angle as the main roof. Then you could deal with the peak of the garage in a couple of ways, from either having a tall back wall, and the peak near the peak of the main house, or a peak in the middle and a shorter roof than the main house.

#3, raise the whole roof so that the peak will be near the wall between the garage and the main house. Your dimensions are not symmetrical. However, the slope on both sides doesn't have to be the same.

There are a few different ways to achieve a vaulted ceiling in the living room. One method is to use rafters hanging off of a center support wall. You don't seem to have that (although the side wall of house which will now between the garage and the house could be made into a supporting wall.

You could also put in a center support beam and rafters.

There are also some truss designs that will give the effect of a sloping ceiling, that won't be full height on the inside.

Thank you for your input! Your first option (1.) will be the one that I was thinking..... You are right the wall between the garage and the house is load bearing. and would remain (block wall). I was thinking of the roof line being perpendicular for the garage make sense too...

This would create a symmetrical valley as one would see on traditional construction, water would flow properly. However----The 8' bump out may just have to be at a shallower pitch to (tie into the garage) - these trusses would have to be set as they were on the original footprint of the home... I just don't want a "canted valley"... Would this suffice? Yes, the whole roof will be removed.

 

[CliffordK]

I think I saw a video recently about asymmetrical valleys pushing water under one's flashing. Perhaps not insurmountable, but something to keep in mind.

I'm not a fan of low slope roofs, although there are some really good commercial roofing products that will work.

 

[drajj5]

This is why the remodel is happening.. The roof that is on the house now is not even 4/12... This is why 8/12 will most likely be what is going in its place. I didn't want to make a shallower pitched roof but I guess I will have to on the section of roof with the odd 8 foot bump.

 

[JimRB]

You are tearing off the existing trusses when the weather gets better? Visit the good lumber yard or truss company for ideas. Hips an valleys are opportunities for expense and leaks.

On our house I have a 30x36 footprint with the rafters spanning the 30 foot. 36 is east to west. The 22x22 too small garage attaches on the west side of the 36 wide with a setback at the front of the house. Front porch is 36'. North wall is 48 feet long. If I ever commit to building a proper garage the 22x22 becomes a great room with hopefully a laundry room and a half bath. That frees up the former laundry room to become a closet.

 

[Mike sandor]

I think I saw a video recently about asymmetrical valleys pushing water under one's flashing. Perhaps not insurmountable, but something to keep in mind.

I'm not a fan of low slope roofs, although there are some really good commercial roofing products that will work.

So my wife and I are toying with a remodel of our home. Our House is a simple 24x40, 2 bed 1 bath. We agree that we need a second bathroom and would like to add a garage to the footprint of the house. this addition will create some interesting roof lines as the house will (not) have equal dimensions.... The question that I pose, is "probably simple" but I cannot work it out in my head the truss dimensions. I am attaching a pic of the new plan and for those who can help please do!

Old house
24x40 - 4:12 pitch 24' Truss - (simple truss - load bearing through the center).

New house
uses the 24x40 footprint with the addition of the garage and an 8' bump-out....

We would like to vault the ceiling and have a much steeper pitch, 8:12 - (scissor truss - 24') open span across the original footprint. With the garage being 24' deep possibly doing the same. However - The 8' bump to allot the addition of the second bath is messing up my roof-line/valley.

View attachment 848960

Thanks

So my wife and I are toying with a remodel of our home. Our House is a simple 24x40, 2 bed 1 bath. We agree that we need a second bathroom and would like to add a garage to the footprint of the house. this addition will create some interesting roof lines as the house will (not) have equal dimensions.... The question that I pose, is "probably simple" but I cannot work it out in my head the truss dimensions. I am attaching a pic of the new plan and for those who can help please do!

Old house
24x40 - 4:12 pitch 24' Truss - (simple truss - load bearing through the center).

New house
uses the 24x40 footprint with the addition of the garage and an 8' bump-out....

We would like to vault the ceiling and have a much steeper pitch, 8:12 - (scissor truss - 24') open span across the original footprint. With the garage being 24' deep possibly doing the same. However - The 8' bump to allot the addition of the second bath is messing up my roof-line/valley.

View attachment 848960

Thanks

If you stay with the same pitch on both the house and garage, the house ridge line will be higher due to the width of the structure. I added hip roofs all around as it looked a bit better to my eye but gables would work as well. Scissor trusses can be designed to give you the interior pick you require.

 

[CliffordK]

How much snow and ice load do you get in Georgia?

I'm not sure about different slopes. However, 8/12 sounds fairly steep. When you get up close to a 45° angle, the roof gets very uncomfortable to walk on.

 

[KennyG]

Personally I would never go over 6/12 if I intended to be on the roof myself. I'm not sure why you would have problems with 4/12. Roofed properly that should give a long roofing life.

 

[EddieWalker]

Why not move the new bathroom and closets to the left side of the house, where the two bedrooms are?