Houston public schools Superintendent Terry Grier wants taxpayers to approve spending $1.9 billion to build and repair dozens of schools in the district.

But the consulting firm that the Houston Independent School District hired to assess what work needed to be done and how much it would cost visited only 35 of HISD’s 279 schools.

Consultants from the North Carolina-based Parsons Commercial Technology Group Inc. told the school board on Thursday that they used survey responses and a computer model to determine the projects they concluded were necessary.

The work includes about $577 million to replace eight high schools, about $354 million to “replace inadequate facilities” at four high schools, about $259 million to replace and renovate facilities at five high schools and $27 million to build two new high schools.

The projects would require a tax increase, beginning with a 2-cent hike in 2014 that would add $29 to the tax bill for a $200,000 home, HISD estimates. By 2017, the total tax rate would have increased 6.85 cents, upping the bill by $99 per year. (Find other home values and the corresponding increases here.)

Board President Mike Lunceford asked the Parsons consultants during Thursday's meeting whether they actually had visited the schools they recommended be replaced, or were their efforts “just a paper chase?”

Trustee Rhonda Skillern-Jones also asked the consultants how they could know any school’s actual condition if they didn’t physically visit the building.

And Trustee Paula Harris asked why the consultants decided some schools should be replaced even if they recently had major renovation work done, such as upgrades to their air-conditioning and heating systems.

Parsons consultants replied that they visited “most” of the schools they suggested be rebuilt or undergo major renovations. But they did not provide the trustees or the public with a list of the schools they did visit.

Time constraints dictated that Parsons personnel rely on computer modeling and responses by individual schools’ staff members to survey questions about their building conditions, the consultants told the board.

They also said that recent renovation work might not indicate a school’s overall physical state.

In interviews after the meeting, Lunceford and Trustee Juliet Stipeche each said they planned to conduct a thorough review of the bond information that Parsons provided before deciding whether they would support the proposal.

“I just saw it for the first time,” Lunceford said of the bond data. “I want to make sure this is done right.”

Stipeche added that she needed “time to analyze the proposal. It’s complex. I have to critique the evidence and do what’s best for the community.”

Trustees hired Parsons in March for $1.25 million to conduct the HISD facilities assessment.

Grier said it would take “two years” for consultants to conduct in-person visits to every district school. He said, as a former principal himself, those employed within HISD’s buildings know what schools’ true needs are.

That insight is “better than a walkthrough,” Grier said.

To put a bond before the voters in a November referendum, the school must take action in August.

Work on an $805 million construction bond HISD voters passed in 2007 is behind schedule and not expected to be completed until 2014, according to district officials.