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warren_white96

How to build utility room on slab under piling house?

Warren White
5 months ago

Having a 35x60 modular home set on pilings. Due to the lot width I am placing the home on pilings to have space for two cars under the home. Also to get the best view out the back of the home. Underneath the entire home will be a concrete slab. Looking for a site for information on building a utility room on the slab under the home. I am not in the flood line so break away walls are not required. I am just worried about the correct wat to connect the walls to the pilings and connecting the floor plate to the slab eliminating any water problems from wind driven rain under the home. Any help in these areas will be greatly appreciated.

Comments (25)

  • PRO
    Patricia Colwell Consulting
    5 months ago
    last modified: 5 months ago

    Do you mean a room with laundry ot heating furnaces etc what exactly do you mean by a utility room? Mayb some pics of what you are doing for sure and are you allowed to have utilities outsdie the main living space ?

  • PRO
    DeWayne
    5 months ago

    No point in adding to the cost by choosing that construction method. No point at all.

  • PRO
    Mark Bischak, Architect
    5 months ago

    Perhaps the modular home company has suggestions?

    What do you mean by "modular home"?

  • PRO
    BeverlyFLADeziner
    5 months ago

    When I called about purchasing a home to be erected on pillings, I was told it would add $100k to the cost of the home. Why do that if your flood zone doesn't require it?



  • Gina Gilgo
    5 months ago

    In coastal areas subject to storm surge, storm surge can be much higher than the regulatory flood zone. Our house is on pilings and we have what is essentially a yard shed under our covered deck. It is in the flood zone so has vents to allow the stornm

  • Gina Gilgo
    5 months ago

    Water to flow out. I don’t know how the walls are attached to the pilings unfortunately.

  • David Cary
    5 months ago
    last modified: 5 months ago

    Piling construction does not have to be that expensive. But it does have downsides - mostly stairs to carry up groceries. Entrance into house has to be carefully planned for furniture. In beach communities, cranes to move furniture are quite common. You get bonus points for a bad idea if your entrance is uncovered by the house. Carrying up groceries in the rain on wet steps is not fun and I would certainly not expect delivery people or the mail man to do that.

    You have more issues with insulation since you don't have the ground to help a bit. This comes into play for water also. Water has to travel up the piling in unconditioned space. So you better not having freezing as an issue. Even cold weather gets your pipes really cold. There is nothing fun about 45 degree water in the morning. You can insulate for this somewhat but it takes a lot of insulation to prevent water freezing in a completely unconditioned space.

    But building a storage room using pilings as corners is really easy. That is the least of your worries. Getting it to code for actual equipment is a different and local manner.

    I am guessing you are near the water but high enough to not be in a flood zone so that local piling installers are common and easy? When I priced out modular on pilings, it was cheaper to stick build but each situation is different.

    Don't forget stairs to get into you back yard. No fun if you have a dog that gets injured or arthritic. Or kids to worry about falling down stairs that are wet. Or being able to watch kids/dogs in back yard.

  • KR KNuttle
    5 months ago

    If I were faced with the problem I would bolt 2X4's to the pilings that went from the floor to the floor of the house. I would then attach a 2X4 that ran between the pilings attached to the floor with bolts. I would liberally apply a proper sealant to the underside of the 2X4 and the floor before I fasten it into place. I would then run another 2X4 a long the underside of the house plumb over the one that i placed on the floor. Once this is complete I would build a standard 2x4 wall attaching it to the 2X4 on the floor, underside of the house, and to the ones on the pilings . I would then add siding and if you would like insulation and such on the inside.


    Once I had drawn up a plan I would take it to the county for the approval and get a building permit.

  • PRO
    Norwood Architects
    5 months ago

    Pouring a slab isn't usually a d.i.y. project. So, I would contact contractors in your area to get advice and a quote. Good luck!

  • PRO
    Mark Bischak, Architect
    5 months ago

    Doing DIY projects that should not be a DIY project reaps great learning experiences, more than you want to learn. Believe me I know.

  • KR KNuttle
    5 months ago

    DIY project are a great learning experience. Make you plans, review them thoroughly, and possibly with some one who knows what they are talking about. People at Lowes, Home Depot, and your local hardware store are a great source of information. Don't be afraid to get multiple opinions on you question.

    Then proceed slowly and measuring every thing at least twice before you make any cuts. In my proposal above, the most difficult thing would be to power nail or drill the holes for the bolts in the concrete. Do it slowly and make sure you don not put yourself in a dangerous situation. If you don't the hospital bill may be more that the cost of contractor doing the project,


    When you are done you can tell all your friends who spend their time playing computer games, "Look what I did"

  • PRO
    Patricia Colwell Consulting
    5 months ago

    I love it whaen we take the time to answer and get no feed back from the OP

  • PRO
    Patricia Colwell Consulting
    5 months ago

    LOL Happy Holidays Mark.

  • cpartist
    5 months ago

    Why pilings versus concrete block?

  • Warren White
    Original Author
    5 months ago

    Thank you for everyone's concern of why I am using pilings. Let me try and answer. My home will be almost as wide as my lot. I want a two car garage and do not want it in front or behind my house. The home will be water front where a river meets the intercoastal waterway. Even though I am way ab

  • Warren White
    Original Author
    5 months ago

    Above the flood zone the extra height will give me a view of the ocean also. The pilings will be comparable to the price of a stick built garage. Thanks to KR Knuttle for actually addressing my question.

  • David Cary
    5 months ago
    last modified: 5 months ago

    CP - in our area (mainly the state of NC) - concrete block is not allowed. That is my understanding and I certainly could be wrong. But having built on the coast, pilings are the default.

    Concrete is somewhat less of a sustainable material compared to wood. It becomes quite damaging when thrown around by wave action. We can have slabs under piling but they have to be cut into small areas to minimize the missile effect upon their destruction.

    Florida goes in an entirely different direction on this issue.

    OP - you should probably have said waterfront in the first place. Where I am on the coast, the ground is above BFE but we are still required to build on pilings. Our shed is just 2x4's and sheathing covered with siding. We have flood vents also which probably are not truly required but at some point it wasn't a battle I bothered having with the permit office. The slab which we already had under the house is the floor.

  • PRO
    Mark Bischak, Architect
    5 months ago

    When an OP does not provide all the information needed to properly give advice they can expect comments that do not directly address their concern, and few people like playing the game of twenty questions. At this point we can assume only the OP knows what the pilings will be made of; steel? block? wood? concrete?

  • PRO
    Patricia Colwell Consulting
    5 months ago

    Sorry but that reply did not answer any of our uestions and Knuttle did not tell you how.

  • PRO
    DeWayne
    5 months ago
    last modified: 5 months ago

    Lots of rules and regulations for waterfront. Be sure you bone up on ALL of that before planning anything. Getting stopped and fined halfway through isn't going to do your end budget any favors. Like is the modular actually built to high wind requirements? Will the shed have storm vents for water flow through? What's the environmental impact of having a giant crane lift all this to place it? Etc.?


    Waterfront IS a flood zone. Unless you are on the top of a bluff. In which case, you wouldn't need to build on pilings for a view. There's also height restrictions and view ordinances that prohibit you blocking the view of the people behind you. So that's another thing to account for. In your architectural planning.

  • cpartist
    5 months ago

    CP - in our area (mainly the state of NC) - concrete block is not allowed. That is my understanding and I certainly could be wrong. But having built on the coast, pilings are the default.

    Yes but he implied at first he wasn't in a flood zone which is why I asked the question. :)

  • Warren White
    Original Author
    5 months ago

    Thanks to everyone for the responses. This home is in NC. There is a home on one side of me built on blocks with a crawl space. and the house on the other side of me and every other home along this shoreline is on pilings. All the homes are pretty much at the same elevation. I have had an elevation survey done which was required for insurance purpose. I am not required to have flood insurance do to its elevation. the home on blocks did not bother with a garage. even though they have a much larger lot. almost all the homes in this area are on pilings and the underneath is enclosed to provide for tool shed and garage space. Contractors will be doing all the local work. I was mainly just trying to get the best advice on attaching to the concrete slab at a later date. I figured I could do that work myself . I can already hear the comments coming on how I wont save any money and should let the contractor do it all LOL. For #$%^ and giggles lets just say I do it myself what is the best way to connect the bottom plate to the concrete slab so that the plate and the sheathing doesn't rot.

  • PRO
    DeWayne
    5 months ago

    Standard construction practices are used to connect a sill plate to a slab. If you know anything about construction, you know how that is handled. With pressure treated lumber, first of all. But you are also back at seismic and high wind requirements, as well as flood venting flow through components. Your local municipality will tell you what they want to see.


    Those adjacent houses are not elevated just for the heck of it.

  • Warren White
    Original Author
    5 months ago

    Thanks DeWayne I will get the information I need from my local municipality when I apply for permits.