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mtassinari

Gambrel roof on cinder block foundation?

mtassinari
8 years ago
I have a cottage in MA that has a semi-dormer on a cinder block foundation (see attached). I would like to put on a gambrel style roof to increase the head room in the attic. Can I do that without changing the current foundation of cinder blocks? I am trying to avoid jacking the house and needing to pour a whole new foundation. Thoughts?

Comments (16)

  • PRO
    Byrne Design Associates, Inc.
    8 years ago

    In general, it looks like adding a Gambrel roof should not be an issue, however, cinder blocks are suspect if they have any signs of breaking down. I would agree tihe the previous pro who suggested getting in touch with a local architect or engineer to have the blocks evaluated,

  • Paul
    8 years ago

    To give you a third opinion, I would agree with the previous commenters, a professional should look at it to be certain. Something else to consider is the soil and footing. The foundation carries the load of the house down to the footings, which, in turn, spreads the load out and bears on the (undisturbed) soil. I would be concerned that a cinder-block foundation could have undersized footings but not necessarily, so it should be looked into.

  • hellen54
    8 years ago

    We had a gambrel roof on a brick home and had a terrible time selling it because of the roof style. Unless you really, really love gambrel , be prepared for folks telling you your place looks like a barn....we did love the style ourselves but would not do it again...

  • Phyllistine Mosley
    8 years ago

    Is this not a good idea if you want space and no additional cost of a third floor? We want to build a lake home in Clarksville Va and need three bedrooms for the family and a basement walkout for guest and possible rental option with a bunk room and a bedroom with large family and kit.Any suggestion ?

  • miacometlady
    8 years ago
    I would consult a realtor first to see if changing roof would be sinking too much money into this cute house for the neighborhood. You may not get your money back. If you are considering changing out roof, perhaps change the pitch of the roof instead of the design. Or perhaps beef up current dormer or add another one on the other side of the roof. In the end it's the structural engineer, as noted, who will make the call as to what your home can handle. Be prepared. You may open up a can of worms if your current foundation is no up to code. Good luck. Keep us updated.
  • Phyllistine Mosley
    8 years ago

    Oh no I was just asking about a Gambrel roof design not this house. My house will be new construction at the lake . It will be like the design on the right of the picture shown.I was interested in your comment on resale of this type of house.

  • Phyllistine Mosley
    8 years ago

    The house on the right is there a floor plan or the dinner? I like this. It will answer my desire to have two bedroom suites facing the lake

  • miacometlady
    8 years ago
    Phillistine- I was not answering your question. You should really start your own post so you can get the attention you deserve. Having two conversations on one thread started by another person is... Well... Very confusing as you can see. If you like something you see on Houzz, take it to an architect and structural engineer.
  • Phyllistine Mosley
    8 years ago

    OK will do Iam new at this and the concern is one I have so I will copy and get back to you Thanks

  • PRO
    GPR Company
    8 years ago

    Changing the roof style, while keeping the same footprint, will not effect the foundation. However, if the style of the roof, changes the bearing points, you would need additional support, in addition to the current foundation. If the new roof will bear on the outside walls of the dormer, then you are good.

    The condition of the foundation would be a separate issue. If there are defects or cracks in it, those should be addressed to make sure it is carrying the current structure load.

    Good luck.

  • PRO
    HERE Design and Architecture
    8 years ago

    Based on the fact that you are likely to need to add framing for the second floor and additional roof perimeter (because of the change of shape) along with probably using heavier members to contain insulation, I believe that the comment from GPR may not be as well-considered as they might have intended.

  • PRO
    GPR Company
    8 years ago

    I believe, based on the information provided by author, our contribution is accurate.

    Here, please keep your responses fact based and not directed at other contributors.

    Much appreciated.

  • PRO
    HERE Design and Architecture
    8 years ago

    GPR, this is not a matter of fact but a matter of judgment based on facts that we do not have and likelihoods based on my experience. My concern was that the homeowner not take what was said as true and proceed without benefit of the study of a qualified design professional. Certainly, by adding what is effectively a second story, they are adding to the loads involved. I don't know what part of the country you live in, but, where I come from, second stories involve more substantial foundations.

  • PRO
    GPR Company
    8 years ago

    "Here" Let it go. Author is looking for preliminary insight, not final conclusions. Owner would need local building permits at minimum. All designs and calcs would be reviewed. These discussions are meant to be helpful, not an opportunity to show superiority.

    Enjoy your day.



  • PRO
    Classical Traditions
    8 years ago

    This comment is directed straight to mtassinari and the proposed remodeling from a one-storey pseudo ranch style to a two-storey Dutch Gambrel in Massachusetts. I lived in Massachusetts for many years and started my practice there in 1973 until 1979, so I am very familiar with the Dutch Gambrel and even designed a few of them in those six years. From my experience, they are popular in many rural and suburban areas of New England, but not in large urban areas.

    To expand any home from one to two storeys, you need to determine the weight bearing capacity of the foundation. You mentioned a "cinder block" foundation. Unless your house was built before World War 2, chances are that it was not built with cinder blocks. That nomenclature is commonly used when referring to "concrete blocks." There is a big difference. Cinder blocks were used in the first half of the 20th century and were quite common, but not as strong as concrete block. Today's concrete blocks are much more sturdy, hold more load-bearing capacity and if installed correctly, can last centuries. Cinder blocks are no longer manufactured.

    More important than the foundation walls are the footings. The weight bearing capacity of the soil usually determines the size of the footings. Generally, a one-storey home with a full basement will require a 10" high by 20" wide solid concrete footing with two #5 rebars. A two-storey home with a full basement usually requires a 12"x24" footing with three #5 rebars. A local structural engineer can perform the required services to determine whether your foundation can support the changes you desire. Building a house on clay and hardpan is better than building on sand and silt.

    Adding a second storey can virtually double your floor area and look quite handsome. The Dutch Gambrel can accomplish your goals if designed properly. When searching for a qualified design professional, be sure to inquire as to his/her qualifications. This is not a design case for homeowners to undertake. Have it done properly and you can expect good results. Be sure to have a qualified real estate appraisal prior to getting design and construction quotes. Make sure that you will get a good return on your investment. Also, be sure you can afford to be living elsewhere while your home is gutted and rebuilt. The entire roof structure will need to be removed, rendering the house uninhabitable for a period of months. The interior of the existing house will need to be stripped down to the bare studs to determine if the wall structure is designed to support a second storey.

    I wish you well in your proposed endeavor and hope you can achieve the desired results. If you have any more questions, please feel free to ask me.