Posted on Sep 06, 2017

Caveat: This is not legal advice but simply information we are providing to help give you a general idea as to whether you may need to elevate your house if you were “substantially damaged”.

To determine this, first you will need to determine if you home was “substantially damaged” which means the cost of repairing or replacing your home is greater than 50% of the value of the home (just the value of the structure not the land).  If your home was substantially damaged, then you will need to comply with the new building code standards. To determine if you must elevate your home above the base flood elevation line, you will need either a Topographical Survey or Elevation Certificate.

This article assumes that you were substantially damaged by the flood and, thus, will have to comply with the new building codes. The main building code rule that applies here says: “Minimum flood protection elevation shall mean the base flood elevation plus 12 inches.”

In layman’s terms this means the first floor of your house must be 1 foot above Base Flood Elevation (BFE) as determined by the Flood Insurance Rate Map (FIRM).  Here is a link to the Houston Building Codes that apply:

https://edocs.publicworks.houstontx.gov/documents/flood_plain/chapter_19_guidelines_floodplain.pdf.

Please note that depending on your zone you may have to build a little higher, but the foregoing rule applies to most houses in Houston.

Tutorial: Determining Your Home’s Base Flood Elevation (BFE)

To figure out your BFE and whether your lot is above or below the BFE you can use the following website:

http://www.gims.houstontx.gov/portalWS/MainPortal.aspx

Once you get to this page, click GIMS (Public)

houston-gims-1

Note: The GIMS application requires that you download Microsoft Silverlight. However, Silverlight does not work on Google Chrome. So, to access it you will need to:

For PC

  • User Internet Explorer
  • Install the Silverlight Plugin when prompted

For Mac

  • User Safari
  • Install the Silverlight Plugin when prompted
  • Open Safari, click on “Safari” in the menu bar and go to “Preferences”. Click on the “Security” tab. Locate Internet Plug-ins and then click Plug-in Settings. Then select “On” in the drop-down. Then click “Done”:

    silverlight-mac-safari

Please note, it takes a while for the map to download with all of the features. But after it downloads the first time, it gets faster afterwards. Once it loads, you will see the screen below:

houston-gims-map-screen

You will want to click on the following:

  1. Click on the binoculars and enter your address:
  2. gims-address-1

  3. On the right hand side of screen, click on Floodplain Data and on Topography (if the drop down menu on the right goes away click on the stack of papers in the top right-hand corner)
  4. gims-flood-topo

Again, every time you click on a button the system will try to load data so just be patient while it loads which can take a while.

After you click on these buttons, you will see a thumbtack on your house and a box on the left side with two tabs. One will say Flood and the other will say Topography.

Click on the “Flood” Tab and check the box that says “Base Flood Elevation”:

base-flood

Then click on the “Topography” Tab, and then click on all three boxes shown below:

topo-tab-select

Once you have all of these options selected, the map will look like this:

map-final

How you put all the info together:

  • The red lines shown on the map are the BFE (please note that the redline is an estimation and will only give you a general idea). So for example, for 4127 Tartan it shows that the BFE is 51 feet.
  • The brown lines shown on the map are the base elevations for the lots. So according to this map the base elevation for 4127 Tartan Lane is 48 feet.

This means that if the homeowner was flooded and substantially damaged then the homeowner will most likely have to raise the house at least 4 feet to comply with the Houston Building Code standards.