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Porch construction question

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Apr 18, 2013, 07:26 PM
mikem201
Porch construction question
Hi,

I have a concrete from porch on a brick base. Above is a roof overhang. I'm trying to figure out how it was constructed. Its a one story house. I will attach a picture and if someone can give me their opinion I would appreciate it. I attached a picture of my house.


Apr 18, 2013, 07:45 PM
redoverfarm
Just a shot in the dark but I would say that there is a block substraite behind the brick. The brick is like the house only used as a veneer. The concrete is formed up on the block/brick foundation and poured with what appears to be a lip. The post most likely are attached with wedgebolts, simpson brackets or other fastners. I doubt they are free standing. They support your porch roof.
Apr 18, 2013, 10:20 PM
Jaybee
The porch roof is only supported by the house and those two corner posts. There are two ways it could be supported:

1. There is a fairly substantial header running between the tops of those two posts. With only two points of support, that header is probably a double 2x12. Ceiling joists then run from the house to the header. Porch rafters built o top of that.

2. Instead of relying on a header between the two posts, two shorter support beams or on each side - running from the house to each post. While there still will need to be a header between the post on the front plane, the rafters of the roof structure are attached to both of the side beams that carry the load. Ceiling framing doubles as collar ties.

This message has been edited. Last edited by: Jaybee,


Jaybee
Apr 18, 2013, 10:33 PM
mikem201
so your saying the ceiling joists are running from inside the house and extended out to meet the header? As far as the concrete porch its sitting on a brick base or just a veneer around the base?
Apr 18, 2013, 10:36 PM
mikem201
quote:
Originally posted by redoverfarm:
Just a shot in the dark but I would say that there is a block substraite behind the brick. The brick is like the house only used as a veneer. The concrete is formed up on the block/brick foundation and poured with what appears to be a lip. The post most likely are attached with wedgebolts, simpson brackets or other fastners. I doubt they are free standing. They support your porch roof.


How are footings usually constructed for a porch like this? Is it a trench type footing along the peremiter of the porch then brick laid on the footings?
Apr 19, 2013, 03:59 AM
Jaybee
To answer your last two posts:

1. I don't know which way the ceiling joists are running. If I had to be nailed down to one guess I would expect that it's option #2 in my post above - that the ceiling joists are also acting as collar ties and are running parallel to the front wall of the house.

2. You will have a trench type footing all around the perimeter of the porch. The porch foundation could be either block faced with brick or just a double layer of brick. There is fill dirt inside that has likely settled and a solid concrete slab that is poured on top. I would put my money on it being a block foundation faced with one layer of brick, as solid brick foundations started going away a long time ago.

You can find the answer here by looking in the crawl space of the house. If there is block on the inside, then block would also have been used on the porch foundation. If there is brick on the inside of the crawl space, then you have an older, solid brick structure.


Jaybee
Apr 19, 2013, 08:18 AM
Sparky617
It is fairly common in new construction here to go with a double layer of brick on top of block foundations for the part that shows. The top row of brick is also solid to help form a barrier for termites coming up inside the block. The brick that doesn't show could be a concrete rather than clay brick but not always. My own house has poured concrete with a brick veneer because I have a basement. My own front porch has a slightly unusual construction, we put a contract on the house after the foundation was poured. We were only to have a stoop for which the foundation was poured. We added a larger front porch with a roof so to enlarge it they used steel decking, like used for bridge construction or concrete floors in multi-story office buildings and poured a larger slab overtop of the steel decking, that was cantilevered over the existing foundation. The brick facing was laid on top of this slab and the finished slab for the foundation was poured inside the brick facing.

The depth of the footer depends on your location, around here it would need to be about 18" to the bottom unless the soil at that level was fill. In colder climates it could be as deep as 4 feet to get below the frost line. From the footer to grade it is is very likely block construction. Your other post indicates that your house is built on a slab, where are you located? The United States doesn't give us a lot of detail on the footer requirements for your house.


General Disclaimer

Any advice given here is general in nature and is not necessarily valid for your given area. If in doubt check with your local codes enforcement department for what is required when doing electrical, plumbing or structural work on your house. Permits may or may not be required in your area and home owners may not be able to DIY some tasks. I have no way of knowing if you have the skills needed to complete the tasks you are asking about, when in doubt seek professional assistance.

My advice may be worth exactly what you pay me for it. :-) For the record I did not stay in a Holiday Inn Express last night.
Apr 19, 2013, 09:07 AM
mikem201
quote:
Originally posted by Jaybee:
To answer your last two posts:

1. I don't know which way the ceiling joists are running. If I had to be nailed down to one guess I would expect that it's option #2 in my post above - that the ceiling joists are also acting as collar ties and are running parallel to the front wall of the house.

2. You will have a trench type footing all around the perimeter of the porch. The porch foundation could be either block faced with brick or just a double layer of brick. There is fill dirt inside that has likely settled and a solid concrete slab that is poured on top. I would put my money on it being a block foundation faced with one layer of brick, as solid brick foundations started going away a long time ago.

You can find the answer here by looking in the crawl space of the house. If there is block on the inside, then block would also have been used on the porch foundation. If there is brick on the inside of the crawl space, then you have an older, solid brick structure.


actually the joists are running perpendicular to the front wall of the house. I have a basement no crawl space. So, the ceiling joists are extending out from the house and are tied into the porch beam?
Apr 19, 2013, 09:43 AM
Jaybee
quote:
Originally posted by mikem201:


actually the joists are running perpendicular to the front wall of the house. I have a basement no crawl space. So, the ceiling joists are extending out from the house and are tied into the porch beam?


If you have verified that the ceiling joists are perpendicular to the house, then that question is answered. The rafters are definitely running in the opposite direction and likely have some collar ties for support. But yes, sounds like the ceiling joists tie into the front header that is supported by the two corner posts.

The small 'door' next to the driveway fooled me - looked like a crawl space entrance. Is your basement finished? The same thing holds true - if you go into your basement and see concrete block then that is likely the make up of the porch foundation too. Other option is a poured concrete foundation faced with brick. You are the best one to determine what the foundation is at this point.

This message has been edited. Last edited by: Jaybee,


Jaybee
Apr 19, 2013, 10:08 AM
mikem201
quote:
Originally posted by Jaybee:
quote:
Originally posted by mikem201:


actually the joists are running perpendicular to the front wall of the house. I have a basement no crawl space. So, the ceiling joists are extending out from the house and are tied into the porch beam?


If you have verified that the ceiling joists are perpendicular to the house, then that question is answered. The rafters are definitely running in the opposite direction and likely have some collar ties for support. But yes, sounds like the ceiling joists tie into the front header that is supported by the two corner posts.

The small 'door' next to the driveway fooled me - looked like a crawl space entrance. Is your basement finished? The same thing holds true - if you go into your basement and see concrete block then that is likely the make up of the porch foundation too. Other option is a poured concrete foundation faced with brick. You are the best one to determine what the foundation is at this point.


I have poured concrete foundation but no way of seeing the porch foundation from the basement. So, the ceiling joists that tie into the header of the porch. The small gable roof over the porch. How would you say that ties into the ceiling joists?
Apr 19, 2013, 10:51 AM
Jaybee
The framing for the gable roof is mostly independent of the ceiling joists. Since the ceiling joists are running out from the house and tied into the outside band header, all they are doing is the low-load of holding up the ceiling. The rafter system and it's collar ties are attached to the two beams that are on either end - running from the house to the porch corner posts.

It's an assumption, but if you have a poured concrete foundation for the main house then you should have the same as the foundation make-up for the porch. That's just construction that makes sense as there would be no reason to change foundation methods unless the porch was build at a different time. From your pics, the porch appears original to the structure.

You have mentioned that you are trying to figure out how the porch was constructed but you haven't mentioned why. What exactly are you trying to accomplish? Repair? Remodel?


Jaybee
Apr 19, 2013, 12:25 PM
mikem201
so there is a header and to 2 band joists attached to each other and being supposed by the 2 columns? Collar ties are horizontal members to stabilize the rafters, right? These rafters sit on the 2 band headers (joists) basically like a rafter would rest on a double top plate of the exterior wall of a house?
Apr 19, 2013, 05:05 PM
Jaybee
That is it exactly.


Jaybee
Apr 19, 2013, 06:44 PM
mikem201
When you want to create a larger roof overhang you create lookouts, right? I think that is the term.
Apr 19, 2013, 10:09 PM
Sparky617
So I take it this isn't the same house that you posted about in the plumbing section.


General Disclaimer

Any advice given here is general in nature and is not necessarily valid for your given area. If in doubt check with your local codes enforcement department for what is required when doing electrical, plumbing or structural work on your house. Permits may or may not be required in your area and home owners may not be able to DIY some tasks. I have no way of knowing if you have the skills needed to complete the tasks you are asking about, when in doubt seek professional assistance.

My advice may be worth exactly what you pay me for it. :-) For the record I did not stay in a Holiday Inn Express last night.
Apr 19, 2013, 10:26 PM
Jaybee
quote:
Originally posted by mikem201:
When you want to create a larger roof overhang you create lookouts, right? I think that is the term.


It's a lot more complicated than just adding something on. If you are extending out the gable end, then yes, add lookouts. But, to keep things strong they must run back past the existing gable line. Once you have a strong framework extending out over the gable end, you can add roof decking and extend the shingles.

Adding a longer soffit overhang is much more complicated. You basically need to remove the old roof and construct a new, larger version with more overhang. The only other way would be to add shallower pitch 'wings' on either side which would look silly on your house.


Jaybee
Apr 19, 2013, 10:31 PM
mikem201
quote:
Originally posted by Jaybee:
quote:
Originally posted by mikem201:
When you want to create a larger roof overhang you create lookouts, right? I think that is the term.


It's a lot more complicated than just adding something on. If you are extending out the gable end, then yes, add lookouts. But, to keep things strong they must run back past the existing gable line. Once you have a strong framework extending out over the gable end, you can add roof decking and extend the shingles.

Adding a longer soffit overhang is much more complicated. You basically need to remove the old roof and construct a new, larger version with more overhang. The only other way would be to add shallower pitch 'wings' on either side which would look silly on your house.


If you wanted to add more soffit overhang I was told you can sister 2/3 of a rafter to the existing and extend it out to create a larger overhang. What do you mean about running them bac past the existing gable line?
Apr 19, 2013, 10:32 PM
mikem201
quote:
Originally posted by Sparky617:
So I take it this isn't the same house that you posted about in the plumbing section.


no this isn't the house.
Apr 20, 2013, 09:50 AM
Jaybee
quote:
If you wanted to add more soffit overhang I was told you can sister 2/3 of a rafter to the existing and extend it out to create a larger overhang. What do you mean about running them bac past the existing gable line?


This is correct. This will extend the width of the roof out each side by whatever amount you wish to add. However, it will also lower the soffits the further out you go so there are limits as to how far you can extend.

My comments about passing the gable end would be if you wanted to extend the roofline outwards (adding on to the front of the roof facing camera).

Again - What is the end result you are trying to get here? This is a long thread and I have no clue as to what you are trying to do, makes giving any advice more of a guessing game. Do you want to make your roof bigger? Do you want to enclose this as a porch? Do you want to change the exterior look? What is it that you are trying to do?


Jaybee
Apr 20, 2013, 02:00 PM
mikem201
Just trying to increase my knowledge that's all. Is it ok if I ask you questions?