Sagging porch on 111yr old house!


Old 09-07-20, 08:55 PM
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Sagging porch on 111yr old house!

Hi everyone,

My name is Andrew and I'm new to the forum because I am having trouble solving a design problem repairing the structure under the porch of our very old house. Basically what I want to do is put a four-pier system in place rather than the previous 2x4-wall-with-a-couple-4x4's-on-a-10x10-concrete-swath system that has slowly settled causing cracks in the wall and an uneven surface inside. It looks like this used to be an outdoor deck that got enclosed and added to the main living space inside. My guess is this was done 20-30 years ago. I would do it without a permit and complicated design process because I generally have a good idea what to do, but we want to sell the house next summer with a clear conscious and not run into trouble over not getting a permit.

The problem I'm running into with the city is that the building codes are not clear to me on a couple things and the plan reviewer assigned to my project has been very unhelpful (and downright rude to me on the phone, claiming this isn't a project for the weekend warrior) in explaining some technical knowledge in layman's terms. I have uploaded my current sketches for building plans the plan reviewer has rejected.

This project has three phases:
  1. Repair support structure.
  2. Replace siding from the roof down. This whole area was not built right, and thus the siding has gotten a ton of water behind it leaving rotten chip board and water damage/settling to the support structure.
  3. Rebuild deck to front door.

What I need help with specifically is:
  1. How can I cover the open space between the floor and the ground without having to dig a trench 42" inches around the perimeter? I don't see why I can't run a 2x4 treated wood wall in between each post and cover it with treated plywood. I initially submitted a plan showing a small concrete base under the wall (that specifically said non-load bearing) and they rejected that. Then I thought maybe we could just run a 4x4 along the ground, but attached to the 6x6 posts. One of the city's comments says this has to go below the grade though, so I'm stumped about what to do here. I haven't submitted that yet because the plan reviewer said I need to have a real plan the next time I submit something, which is why I'm asking for help. I want this to be a ventilated crawl space that basically keeps the elements out - snow, rain, critters etc. Can I put a couple small vents and avoid them claiming it's a conditioned crawl space?
  2. The north wall is 4' from the property line and the city has a requirement to have a 1hr fire wall for any walls less than 5' from the property line. How do I have a fire barrier that can go all the way to the ground? Cement board? Can I do that on the lowest part of the wall and use 5/8 exterior gypsum for the rest of the wall or does it have to be the same system all the way around?
  3. Can the city require me to bring the insulation of the floor up to code (R-30 in our area)? Why do I have to insulate the floor and have a vapor barrier when I'm just fixing the support structure to it, not changing anything about the floor specifically. If they can, the only solution that is any good is to put 4.5" of foam because the floor joists are 2x6. I have one quote for about $1000 on that which I am hesitant to say yes to until I know for sure we have to do it. I will get one or two more quotes if we have to go that route.

I am already in the middle of fixing the support structure because I thought getting a permit would be an easy task and I didn't want to watch it sag and settle any further (potentially causing damage I couldn't fix myself). I started cutting things open a month ago because I wanted to finish everything long before it gets cold. I have the 2x6 sandwich beam in place with 4 jack posts that I've been able to restore a level floor inside with. Just need to get the permit issued so we can dig and get the footings down. My budget for this project was to keep it under $2000. If we have to do the foam spray insulation it will be more than that, but that's the only reason it would end up significantly above that. If anyone can steer me in the right direction with the issues above that would be greatly appreciated!


This is what it looked like before. You can see it sagging on the right (south) side.

Here's an example of the water damage (with my dad helping this day.)

I got the 2x6 double header board in place over labor day weekend.
Attached Images
File Type: pdf
File Type: pdf
Porch Wall Section plan.pdf (425.9 KB, 6 views)
File Type: pdf
Site Plan.pdf (161.6 KB, 7 views)
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Old 09-08-20, 01:07 AM
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How can I cover the open space between the floor and the ground without having to dig a trench 42" inches around the perimeter?
So your heading to a point of confrontation with your local building code, you have no plans, yet your making repairs and chances are your going to get a cease and desist letter.

Your on their radar screen now and you need to see an Architect and figure out what it's going to take to do this repair correct.
Old 09-08-20, 02:03 AM
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Welcome to the forums Andrew!

Whether you use 6x6 posts or concrete blocks they need to be supported by a footer that is down to the frost line. Generally the insulation, wiring, etc. only has to be updated if that portion of the job is being redone BUT it's also somewhat dependent on your local inspector.
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