The Secret Service is adding a second layer of steel spikes to the top of the White House fence to keep would-be intruders at bay, according to a proposal submitted to the National Capitol Planning Commission.

The steel "pencil point" spikes will be snapped into place at the top of the fence and protrude outward, according to a diagram included in the proposal submitted for the Secret Service by that National Park Service. The commission approved the proposal at a hearing Thursday afternoon.

The spikes will be added to the fence along the north and south sides of the White House grounds starting Friday, the Secret Service and National Park Service said in a statement Thursday.

The Secret Service has been studying ways to improve security at the White House since a Texas man was able to climb over the fence and run deep into the executive mansion in September.

The agencies said a preliminary review of design concepts for long-term security changes at the fence is being reviewed, and a final design is expected to be selected this summer. The final design will be submitted to the planning commission and the Commission of Fine Arts, and construction is expected to begin in 2016.

In a nine-page summary of the incident, the government concluded that Omar Gonzalez cleared the fence in a spot where a steel trident, or ornamental spike, was missing. A variety of other security failures, including poor training, were also highlighted in the report.

A second report from an outside panel recommended that the Secret Service replace the 7 1/2-foot tall fence around the 18-acre White House complex. In the interim, the agency charged with protecting the president and securing the White House placed temporary metal bike racks along the fence line to keep people away from the fence. The proposal submitted to the planning commission did not discuss the bike racks.

Since the September incident, there have been several attempts to climb over the fence. In April, a California man was arrested after successfully scaling the fence and getting on to the White House lawn.

The Secret Service will also start work Friday on changes to vehicle checkpoints at the White House complex. The agency said the work will include work to officer booths. Security changes at the checkpoints are expected to be completed in early July.