CountryPlans Forum

General => General Forum => Topic started by: Rob Baker on March 25, 2005, 09:36:23 PM

Title: Boathouse Foundation Repair
Post by: Rob Baker on March 25, 2005, 09:36:23 PM
I was wondering if anyone had any suggestions as to what type of foundation I should install to help support an existing 20' W x 40' L boathouse that has an ice damaged concrete block foundation. It is on a sloping grade, with the lower edge at the waterline and the back end of the house at 8'-0" above the waterline. I'm not sure what type of foundation will survive being underwater 1/2 the year along with ice pushing up against it in the winter. I would like to do the work myself as trades are scarce in the area. Your comments are much appreciated.
Title: Re: Boathouse Foundation Repair
Post by: glenn kangiser on March 26, 2005, 01:16:22 AM
That sounds like a tough one.  Are there other successful foundations in the area you may be able to copy?  Other than that, it sounds like you may need the assistance of a local engineer familiar with what works.  He may be able to design something you can do yourself if you mention your desire to do that as he checks the job out.
Title: Re: Boathouse Foundation Repair
Post by: Rob Baker on March 26, 2005, 10:49:14 AM
Thanks for responding so quickly.

The only boathouse on this lake is of a similar construction, (conc. block w/ footings) but is set back from the waterline by about 15'-0". It does not even come in contact with the lake. And recent by-laws have prohibited the construction of new structures within 50' of the high water mark, which is why I have to build on the same footprint.

I was thinking about maybe augering a 5'-0" to 6'-0" hole and putting in a sonotube at each front corner. But I don't know if that's enough. And what do I use as a vertical support...steel I-beam? 8" x 8" cedar posts?

I appreciate any suggestions.

Title: Re: Boathouse Foundation Repair
Post by: glenn kangiser on March 26, 2005, 11:42:09 AM
I am not an engineer so it is entirely up to you to decide whether any information I or anyone else points you to is applicable and you are responsible for the ultimate success or failure of whatever you may do to remedy this problem.  My first suggestion would be to get an engineer to look at it.  That said, in the past I have seen some things you might be interested in.  

General curiosity-- how bad is your ice- your location ???  Do you have digital photos we could see?

The Army corps of engineers has some books on line that may at least give you some ideas.

First links are to possibly pertinent information- last is entire list of manuals.

You may spend a lot trying some of this stuff on your own without an engineers help only to see it fail, but you have to decide that.

Hope some of this helps. ;D

http://www.crrel.usace.army.mil/permanent/ice_crushing/

http://www.usace.army.mil/inet/usace-docs/eng-manuals/em1110-2-1612/c-6.pdf

http://www.usace.army.mil/inet/usace-docs/eng-manuals/em1110-2-1612/toc.htm

http://www.usace.army.mil/inet/usace-docs/eng-manuals/em.htm

http://apache.airnet.com.au/~fastinfo/theory/
Free Information and Literature
Title: Re: Boathouse Foundation Repair
Post by: Rob Baker on March 26, 2005, 06:25:44 PM
Once again thanks for the suggestions...

The location, north of Algonquin Park here in Ontario, is a seasonal one so I'm only able to see the after effects and once the ice recedes, (pressure ridges on the shore, additional movement of the existing foundation, etc...) I'll be back up there in mid-April and will post a few shots then, (if the boathouse has survived that is).