In the aftermath of Hurricane Harvey, big changes could be coming to the way homes are built in Houston.

Mayor Sylvester Turner said Wednesday he wants to force developers to build new homes at least two feet higher than the 500-year floodplain, or the area that has a 0.2 percent chance of flooding in a given year.

Houston has experienced a 500-year flood each year in 2015, 2016, and 2017.

Ed Wolff says three feet of water went inside his Meyerland home during Harvey, double the amount it took on during the 2015 Memorial Day floods.

On Wednesday, he was three weeks away from raising his home by six feet.

“If I elevated it only to the level the city would require, I’d only have to go up about two and a half feet,” said Wolff. “I’m going up six feet because I had three feet of water during Harvey.”

During the weekly City Council meeting on Wednesday morning, Mayor Turner unveiled his proposal to require new homes inside Houston city limits be built at least two feet above the 500-year floodplain.

Turner said the elevation will be done “not by raising the ground beneath new dwellings, but by having the dwelling itself sit higher.”

Currently, new homes within Houston city limits must be built one foot above the 100-year floodplain.

On December 5, Harris County Commissioners passed the same rules for unincorporated Harris County, which is home to roughly 1.8 million people and most of the new home construction since 2000.

Related: Harris County tightens development rules in floodplains

In some areas, the new rules mean an elevation increase of eight feet.

“It we make these changes, it is going to cost us more,” said Mayor Turner after Wednesday’s meeting. “Relatively speaking, it’ll be a lot less than not doing anything, and certainly in the long term, people will be able to say that we are building a stronger, resilient city that can mitigate the risk of flooding.”

Turner also proposed tougher stormwater detention requirements and temporarily allowing Harvey victims to live in FEMA trailers on their property while they make repairs.

“Together, these changes are not the entire answer to flooding in Houston,” said Turner. “To protect ourselves, our children, and our children’s children from future floods, we must also widen our bayous, build a third Army Corps reservoir, and take other sweeping measures that only the federal and state governments can fund.”

Besides being a Harvey victim, Wolff is also the Local Issues Governmental Affairs Chair for the Houston Association of Realtors.

“I think it’s smart,” he said, referring to Turner’s proposed elevation requirements. “I think, again, we need to pay attention to that affordable housing aspect.”

Wolff says he discussed the idea with developers before Harris County Commissioners voted in December.

“It might add another $10,000 to $17,000 in cost to that structure,” said Wolff, basing the figure on the average Houston home price of $270,000. “But in adding that $10,000 to $17,000, if it prevents it from having a major flood event, I think the value offsets substantially.”

Even with that requirement in place, Wolff says his home and many others still would have flooded during Harvey, cautioning that past flooding doesn’t predict future flooding.

Wolff also warns flood maps could change and thinks everyone in Houston needs to carry flood insurance.

Meyerland resident Drew Shefman suffered flooded during both the Memorial Day and Tax Day floods. He significantly elevated his home the day before Harvey struck.

“If you are the owner and you’re doing this not because you wanted to but because you have to, cause that’s the only option you have, I think in this proposal, the city should help out in some ways,” said Shefman.

Mayor Turner said Wednesday there are no current plans to provide grants to homeowners to help with the extra cost. However, he says the plan, if approved by City Council, most likely wouldn’t be implemented until late 2018 so that homeowners have enough warning about the changes.

The mayor said the city will continue meeting with developers and plans to meet with homeowners to get feedback, with City Council voting on the new requirements as soon as mid-February.