Hello, the house I purchased about 10 years ago was built in 95. I live in southern VA. I'm not sure the correct terminology, but I have a concrete slab carport that is suspended above an empty room adjacent to my basement. It has had a sag in it since we moved here. I never park a vehicle on it because I worry about its stability and really don't have a desire to do so if it were fixed. So, it will just be foot traffic and maybe enclosed later to make another room. The carport is about 12' wide and doesn't appear to have any support other than the re bar which is exposed in the center on the bottom side. There is pitting on top and the water pools in the center after a rain. Then it slowly drips into the open room below. Its only sagging a few inches, but it has cracked some and also opened the joint between where the slab lays on the outside block wall. What is the best approach to this? Should I jack it up slightly and put an ibeam across the center? Leave it alone since I won't have any cars on it? Seal the top to prevent retention of moisture? Tear it down and build wood subfloor? Also, I would like to eventually attach a deck to the back. I'm afraid if it sags more over time it will warp my deck. Any help would be greatly appreciated. I can post pictures if that'll help. Thanks!

 

Pictures would certainly help. It sounds strange, to say the least. What's the length of the car port? One I-Beam isn't going to do the trick. What does the ceiling look like in the empty room below? Can you see joists? If so how many are there?

 

good gawda'mighty, it had the sag & cracks when you looked at it and you STILL bought it ? ? ? hope you got a good deal !

conc does have a certain flexural strength & rebar only adds to that strength,,, that being said, either the amount of steel is below what's required, the conc lacks the strength required, or the whole design is wrong - seeing the exposed steel is evidence the steel's in the wrong place as it should be covered ( top & bottom ) by AT LEAST 2" of concrete.

i'm sure its not a difficult repair as your prof engineer ( who specializes in structural work ) will point out - probably some supporting columns, spreader beams, & independent column foundations.

no sense wasting more time on here - save your efforts for real life - this is only virtual,,, so
good luck - hopefully you saved enough on the purchase price to be able to afford this work IF its as you describe, you'll likely not be able to sell it - certainly not in an ' as is ' condition,,, i'd expect even a blind home inspector'll know somethings wrong

 

I think you have several indications that the slab has sagged over time. The best solution for now and the future would be to hire a Professional Engineer to devise a repair and take out a building permit to perform the repairs. That way everything is legal and documented which could be an asset when you sell the home. If you do a DIY repair it may be sound but when you go to sell the house the purchasers may be scared off by the cracks and home grown repair.

 

Yes, I still bought the house. This was not a deal breaker for me. If nothing else, I'll demolish this section and turn into a room or deck. The rest of the house is in great shape. If you have some advice other than I shouldn't have bought the house, I'd love to here it.

I've attached some pics showing the surface of the carport where the water pools, the side view of the the carport, the cracking where the slab meets the block wall, the rear view, and the ceiling of the room beneath.

Let me know your thoughts! I can take more pics. Oh, and the length is approximately 24'.

Thanks!

 

i can appreciate a bargain as, Lord knows, i've bought more than my share the advice still stands - call a pe this isn't diy stuff as in ' you don't want to sue yourself ! '

 

You never mentioned the porch on top of the car port! I suggest that you put a level on that as well.

 

The "porch" is what I'm referring to as the carport. The previous owners parked their car on it. I haven't been so brave. The bottom section just has a dirt floor. I have put a level on it. Its sagging to the middle significantly.

 

BTW. Am I using the right terminology here? I've never seen this type of setup. I wasn't sure what to call it. All of the ranch style homes around here that look just like it are filled in under the carport. I've never seen one with a floating slab like this.

 

I understand now. It's the porch that's sagging. So there are no headers holding the slab, just the rebar in the slab itself. In that case, take stadry's advice.

 

think of it as a bdge deck - they're self-supporting, too, other than the main columns,,, it all depends on the flexural strength ( conc does bend ),,, usually you'll find more than 1 mat of steel & a very 'tight' conc mix design.

we're got 3 conc decks to repair now - all on the 2nd floor,,, cracks, sagging, spalling, etc - big deal - we'll diamond saw out the deck, core drill the 2nd floor slab for new rebar, use stay-in-place forms, & more conc - VOILA ! ! ! more boat payments

 

Personally, I would support the roof over top of the slab and tear off the slab. I would then construct a new floor where the slab use to be with dimensional lumber (treat would be the best) and secure your roof to the new deck. That would be the least expensive, I think.

 

Landfillwizard, that was one of my potential countermeasures. I'd rather not deal with the concrete anymore. I had planned on enclosing the top section at some point anyways. I'll think on it more then make a decision. I may have someone come look at it as well. Thanks!