Flood Mitigation

By John R. Landers Jr. Hercules / JRLJ Enterprises LLC.

Flood Hazard Mitigation Measures

Over the last few years, there has been an increased occurrence of flooding in areas near rivers and coastal areas due to storm surge from natural disasters.  Homeowners who have homes that are in these areas are usually required to buy flood insurance provided by The National Flood Insurance Program (NFIP).  A homeowner can take measures to keep their home from being affected by flood waters, by lifting their home above the Base Flood Elevation (BFE) determined by FEMA and local government regulations.

Not only can homes built on crawl spaces and basements be elevated and lifted above the BFE, but procedures have been developed to lift homes built on concrete slabs.  The following is a description of the procedures to lift a home built on a concrete slab. 

Preparation for the House Lifting
The House Lifting Contractor will cut the sheet rock inside of the house at the 49 inch mark half way up the wall from the floor.  The bottom portion of the sheet rock and the insulation will be removed.  The paneling, tile, tubs and kitchen lower cabinets will be removed.  It is recommended to remove any split jam doors and casings.  Access openings will be cut to allow for steel beams and equipment to be installed.  The House Lifting Contractor will cut a separation line around the house at the concrete floor level on the outside of the house using a concrete saw.  This is a horizontal cut line.  The topside of the line will be lifted.  The structure below the line will remain.  On the inside of the house, House Lifting Contractor will remove any nails or straps or bolts that are securing the plates on the concrete slab.  The plates are 2x4’s that are on the bottom of every wall.  Using a Bobcat skid loader that is a rubber track loader, House Lifting Contractor will unload house lifting equipment from tractor trailers and place it in the staging areas where it will be used for the lift. 

House Lifting Contractor will install the appropriate amount of crib towers on the inside of the house on the concrete floors.  Contractor will then install a matching number of hydraulic cylinders on the inside of each crib tower.  The crib towers will be made from 6 in x 6 in x foot wooden blocks. House Lifting Contractor will then make a grid from steel beams over the wooden crib towers.  House Lifting Contractor will use 2x10 by12,14 and 16 foot lumber to construct a temporary floor system on top of the steel beam grid.  The temporary floor system will be screwed to each stud in the walls.  House Lifting Contractor will cross brace the temporary floor for added stability. 

Unified Jacking Machine
A unified jacking machine is a system that uses hydraulic cylinders connected to a unified hydraulic fluid pumping system to lift houses off of their foundations.  The unified jacking machine allows the house to be lifted uniformly even though the weight may be different in different areas of the house. This keeps the house stable and square.

Lifting the House and Lowering the House / Constructing the Permanent Floor System
Using a Unified Jacking Machine, House Lifting Contractor will lift the house off of the slab.  House Lifting Contractor will lift the house in 12 inch increments until the house has been elevated to a level one foot above the finished elevation.  A licensed surveyor, hired by the homeowner, will determine the necessary elevation of the house above the Base Flood Elevation based on FEMA requirements. It is recommended that the house be elevated at least 8 feet high to allow for the space underneath the house to be utilized as a garage area.   An architect or a structural engineer will need to be hired by the Homeowner to draw a plan of the house as it will exist after it has been elevated. This plan includes the foundation plan and where the foundation piers need to be placed to support the house.  This foundation plan will need to be submitted for approval to the local government building and planning department for approval. 
The house will be held stable on the House Lifting Contractors equipment to allow a new foundation to be constructed under the house. Once the new foundation has been constructed and cured for a period of time, a framing contractor can construct the permanent floor system onto the newly constructed foundation.  Once the new flooring system has been constructed, the House Lifting Contractor will lower the house onto the foundation and the floor can be attached to the stud walls of the house.  The House Lifting Contractor will then remove his equipment from underneath the house.  A Carpenter can then build the steps to access the entrances to the home.  By performing this home elevation, the homeowner can help prevent future damage to the home caused by flooding.