House addition questions

Page 1 of 2  
I am planning an addition to my 2 story colonial. The addition is actually extending first floor along the side facing backyard. The addition will be 50 ft long by 6 ft wide. I want to do as much as I can myself leaving to pro only that part of the job that I absolutely cannot do or make no sense to do myself. I have moderate experience in framing, plumbing, electrical, insulation, drywalling and have all necessary power tools to do the job. I do not have any experience in building foundation or putting joist-beam floor system. I am weighing two options for the addition foundation: crawl space and full basement. Here I have several questions:
1. While I realize that every project has it many specifics what the approximate cost would be to excavate hole for the 50 ft x 6X ft addition foundation, build the foundation walls and slab, backfill and put the floor with no subfloor? I line in Central NJ.
2. What's the approximate cost difference of building full basement vs. crawl space? Frost line in my area is 3 ft so trenches for the footings must be dug 3 ft at least.
3. What's the approximate cost and benefits difference of concrete monolithic vs.cinder blocks foundation? My house (55 years old) foundation is built using cinder block with I believe no rebar reinforcement.
4. Is it feasible both economically and from time perspective trying to do some of foundation work myself? Could you advise me if any of the following foundation tasks I can do myself or I should forget about them and leave them to pro:
- building footing forms and put rebar in them
- renting gas powered concrete mixer or get ready mixed concrete and build footings myself
- building foundation walls using cinder blocks
Is above what I can really do myself or it is not worth it? I have limited experience with concrete (redoing parts of basement slab after installing underslab plumbing)
I believe having foundation built and floor put I can take over enlisting my Dad's and friend's help to put frame, siding, roof, plumbing, electrical and internal finish.
Any comments and advise would be greatly appreciated.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

For any quantity of concrete don't even think about mixing it yourself. It is not just the backbreaking work, it is the quality, consistancy, and time do do it in batches when a pour should be continuous.
There are alternatives to block and the usual plywood form. Look into using insulating concrete forms (ICFs) for at least he foundation if nt for the entire wall. It can be done yourself. Check out www.polysteel.com www.integraspec.com www.reddiform.com www.standardicf.com
Be sure to get up to speed on all the newer engineered wood products available. Not to mention al hte ohter building materials that simplify building. Ed
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Is above what I can really do myself or it is not worth it?
If your time has value, you will be ahead to hire pros.
If your time has no value, how will you pay for materials?
In any case, the first thing you need is a design, from a licensed, local architect.
Best of luck, and let us know how it comes out!
--
Lyle B. Harwood, President
Phoenix Homes, Inc.
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
My time does have value. And although I earned 3 times more then an average tradesmen annually their per hour rate (this is what actually you are paying them) exceeds probably that of some CEOs. In area where I live it is just astronomical. Initially I wanted to hire a contractor to install a sewage ejector pump and change plumbing in my basement when I was building a basement bath. I called several plumbers to get quotes. One said that job was too tough and refused even to consider it. Other gave quotes around $5500. I was shocked. Finally, having no prior plumbing experience but very good understanding what and how to do I did everything myself in three days. I did though made one mistake found by a plumbing inspector and that took me one more day to correct. cost of material was about $200. Besides obvious economic benefits of doing myself there are two others that other people my not share. First I really like building, I enjoy it. Second I hate so much to deal with contractors. I had very little experience with contractors and almost all of it is negative. I would rather learn to do and then do something myself then spend time calling several tradesmen, collecting quotes, bargaining with them, supervising them, etc.
wrote:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Second I hate so much to deal with contractors. I had very little experience with contractors and almost all of it is negative. I would rather learn to do and then do something myself then spend time calling several tradesmen, collecting quotes, bargaining with them, supervising them, etc.
Best of luck, and let us know how it comes out!
--
Lyle B. Harwood, President
Phoenix Homes, Inc.
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
I see you are still on this news Lyle!!!
wrote:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

I doubt I'm the only one that sees this, but you never post anything of value and you always piggyback on someone else's response. Just like that little dog that follows the big bulldog. "Hey, hey, hey Spike! Get 'em Spike, get 'em!" Also, just do everyone a favor and try not to be the moderator of the NG.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Alexander Galkin wrote:

Hi, 6 feet wide? That is really narrow! Would feel like tunnel. Tony
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
The addition itself will add no separate rooms but instead will extend kitchen, bathroom and office. 6 ft extension towards backyard is pretty much what I need.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
First thing to check is if you can submit the plans for the addition yourself (many states allow this under an owner builder provision) or if you're required to have an architect or contractor stamp them. Unless you are in the sticks you probably will be required to have a structural engineer look over and stamp your plans. Also if you're putting in any electrical (probably are) you need to see if based upon the size of your addition, if you will trigger redoing the smoke detectors in your main house as they are probably not all interwired together with building power and battery backup. If you are adding over a certain % of space onto your house usually you have to retrofit the smoke detectors in the entire building.

pro
do
floor
You're going to have to talk to local subcontractors to get their rates, they vary widely. Typically excavators charge by the hour.

must
Concrete and steel in most areas of the country has gone up considerably (steel 3x) in the past year and so the cost difference is probably more than you would expect.

My guess is, if the building codes are anything like in Nevada, you're basically going to build what the structural engineer tells you to build, unless you want to "upgrade" beyond what the engineer requires.

following
I definitely wouldn't be mixing concrete myself, that's not worth hassle, but you may be able to build footing forms and rebar, but the issue is you better be able to lay the forms out completely square and level. Most contractors are using laser levels for this nowdays and not the cheap $50 ones from sears.

my
and
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
I know I need a licensed architect to calculate the load, size and type of headers, etc. I already talked briefly to an architect and also to a building inspector while he was inspecting my other project. So when I will be applying for a permit I will have my plans reviewed and sealed by architect. Regarding electrical I have new 150 A service panel in my house and I will be completely upgrading wiring in kitchen, bath and office that the addition extends. It does not add any separate rooms so I don't think I need more smoke and CO detectors then I already have. They all but one in basement and battery powered and not interconnected. Fire inspection was passed OK.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
In a previous post Alexander Galkin says...

In most states this is illegal. Most states require the plans to be prepared under the "direct supervision" of the design professional. Direct supervision is usually defined as "in the design professional's office".
--
Bob Morrison
R L Morrison Engineering Co
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Building inspector explained to me that structural changes must be approved and signed by a licensed architect. Who prepared them does not matter. I also happen to have a brother-in-law who is a licensed architect though not in my state.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
In a previous post Alexander Galkin says...

Alexander:
I don't know what state you are located in, but the building inspector is not the last word on this issue. In fact, most don't know enough about the state licensing laws and minimum design procedures to put in a teacup. Ever heard of trying to do a "lateral analyst of one wall of new addition". Patently ridiculous! Yet, that was the comment from the building inspector.
I would NEVER put my seal on a set of drawings prepared by the owner. That's a good way to lose one's license.
--
Bob Morrison
R L Morrison Engineering Co
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
I just rcently drew my own house plans and I have an engineer doing the structural plans right now. Not sure if you mean directly stamping an owners drawings or if you mean you wouldn't stamp drawings you drew and calculated based upon an owners drawings, but I had no problems finding several engineers that would take my owner builder drawings and produce and stamp a set of structural drawings and calculations. It was pretty cheap too.
-Jeff

approved
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
In a previous post Jeff Smith says...

Jeff:
The procedure you describe is acceptable and I would do the job that way myself. The OP was describing a scenario wherein he expected the architect or engineer to stamp drawings prepared by the home owner. That is the situation that is not allowed under most state laws.
BTW, I'm glad the process worked well for you. I try to set my fees low enough to encourage home owners to take advantage of having an engineered set of plans. Yet, I don't want to underprice the value of the service received.
I guess I must be doing something right since I have consistently maintained at least a 4 week backlog of work.
--
Bob Morrison
R L Morrison Engineering Co
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

That's a lot of work for an extra six feet! Have you checked with zoning and the building department? Have you worked out the structural requirements for openings in the existing wall? Is there room to move equipment from the street to the back of the house? Is there enough vertical distance to fit a roof below the second story window sills? Do the existing mechanical & electrical systems have capacity for the addition? If the existing basement wall is unreinforced, how is the new wall to be tied to it?
The cost of excavation has to include digging next to an existing unreinforced wall without colapsing it; excavating one large enough to accomodate working room and the angle of repose of the earch; disposing of the extra earth.
There is more that needs to be taken into account before begining and the cost to design the work will be no less than for a much larger addition, since there are some things that must always be done.
Tom Baker
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
First of all thank you for your response.
See below my answers to your questions.

I need six feet to extend kitchen and office. I don't need anything more as I don't want to reduce my backyard by building larger addition.

No I have not applied for a permit yet and my project is in early planning stage. That's why I posted my questions here. Depending on what part of it I will be doing myself I will plan and budget accordingly. I did though speak to a building inspector while he was inspecting my other project. I don't beleive zoning department will have any issues with my plans.

Not yet. I plan to consult and get my plans signed by a lisensed architect before applying for a permit.

I can remove part of the fence that separates back yard from front yard to allow excavator and other equiptment and materials to be moved from driveway to backyard working site. At the same time I want all job to be done as carefully as possible. I don't want entire backyard to be turned upside down. Especially I worry about centures old oaks on my backyard. Although all trees are not in close proximity to the potential building zone I don't want to take chances. Do you have some advise what I should do to make as little damage to backyard as possible? I have no idea what type of excavator is needed. I also don't know how concrete is delivered and poured for the footings. I know there are concrete deliveries with pump that allow to pump concrete for the structure on backyard while truck is standing on driveway. But since that amount of concrete for the footings is relatively small hiring a concrete pump truck might be very expensive. That's why I asked it if it feasible to rent gas powered concrete mixer (my local HD has one). I can then have coarse aggregate, cement and sand deliverd and dumped on driveway. I also leaning to building walls using cinder blocks as they also can be dumped on driveway and I can move them to the work site later.

Yes. Actually, the shed roof I am palnning will have the same pitch as my house roof for the six foot wall extension.

I don't understand what "mechanical" means. I do intend to replace all wiring for the kitchen, bath and office that will be extended. The bath will also be completely renovated and its plumbing will be fully replaced.

I talked to a building inpector and also read in books. Holes will be driled in existing foundation and rebar will be inserted in to them where addition foundation attaches to existing foundation. I do plan to rebar reinforce footings and foundation walls regardles of how they will be built. I also plan to waterproof the addition foundation if it will have full basement but I didn't think yet on waterproofing method.

I understand that. Excavating will be done by a pro.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I could be wrong, but you shouldn't have any problems with collapsing the existing foundation. Once the subfloor is in, which yours has been for ~50 years, an effective box is created. That's why it's normally advised to not backfill until the subfloor is installed. Just don't hit the wall with the hoe.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

In large commercial buildings, excavation next to an existing foundation is a very touchy (and expensive) endeavor, and involves some serious inspection (before and after) and monitoring of the existing structure. I can't imagine it being such a casual job on a residence but I could be wrong.
JTMcC.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Site Timeline

Related Threads

    HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.