How Drawing Review Caught 5 Conflicts on Ohio Student Housing

A Podium Building With 650 Bedrooms Over an Unheated Ohio Garage

An architect and engineer firm was finishing construction documents for a student housing building in Ohio. Five residential floors of wood framing sat over a concrete podium with an open, unheated parking garage. The units were 4-bed, 4-bath suites, with about 650 bedrooms across the building.

Student housing repeats. The same unit plan stacks floor over floor and mirrors across the corridor, so a coordination miss in one unit becomes hundreds of field fixes. The garage below adds a different problem: every system that feeds the building has to cross it.

The firm wanted the gaps between its architectural drawings, its consultants' drawings, and the specs closed before the set went out for permit.

Helonic Found $250,000 to $750,000 in Missing NFPA 13 Sprinkler Scope

The firm uploaded the PDF set and the specifications. Helonic compared the unit plans, the podium structure, and the plumbing, fire protection, electrical, and technology drawings with each other, with the specs, and with the code analysis.

The first finding was wet stacks at the podium. The unit plans stacked plumbing walls through the wood floors. At the podium, the stacks had to offset around the concrete transfer beams to reach the main horizontal drains, which P-102 ran below the podium slab through the garage. A-101 showed a van-accessible route that needs 98 inches of clear headroom.

The stack locations above did not line up with the podium column grid, so the drain offsets clustered where the transfer beams were deepest. The 6-inch and 8-inch mains, sloped at 1/8 inch per foot, dropped below 98 inches along the van route by the far end of the run. Sprinkler mains and garage exhaust duct shared the same space.

Gravity drains cannot simply be raised. The fixes are rerouting mains, relocating accessible parking, which can break the accessible space count, or penetrating post-tensioned transfer beams, which the structural engineer may not allow. The firm priced it at $50,000 to $200,000 in the field to reroute mains, restripe parking, and run a structural review, with 2 to 4 weeks of delay. Fixed before permit, it was $3,000 to $10,000.

The second was freeze protection in the open garage. FP-101 showed a wet-pipe sprinkler system throughout, including the unheated garage. Plumbing ran the domestic water mains to the risers through the garage ceiling.

The fire protection spec called for a dry-pipe or antifreeze system in unheated areas, and the plumbing spec required heat trace and insulation on domestic water in any space that can drop below freezing. The drawings showed neither, and electrical showed no circuits for heat trace or for a dry-pipe air compressor.

In Ohio, the first hard freeze finds that. A frozen sprinkler or domestic main over a garage means water damage, a fire protection impairment, and a building that cannot be occupied until the repair is done. Converting to dry-pipe after install means new valves, a compressor, sloped piping, and different sprinkler heads. The firm priced it at $60,000 to $250,000 in the field, more if a pipe bursts, with 2 to 6 weeks of delay. Fixed before permit, it was $2,000 to $5,000.

The third was NFPA 13R where the building needed NFPA 13. The fire protection spec called for 13R on the residential floors, which is lighter and cheaper because it does not require sprinklers in attics and most concealed spaces. The code analysis on G-002 showed the building past the 13R limits once the podium and the five residential floors were counted.

Under NFPA 13, the attic and the combustible concealed spaces in the wood floor-ceiling assemblies need sprinklers or noncombustible fill, and the balconies need coverage. None of that was drawn, and the fire protection bid was based on 13R.

Found at plan review or after framing, that means adding pipe into closed attic and floor spaces across the whole building. The firm priced it at $250,000 to $750,000, including a larger water supply, with 4 to 10 weeks of delay. Fixed before permit, it was $3,000 to $10,000.

The fourth was Wi-Fi and low-voltage infrastructure. The technology spec required a wireless access point in every unit, a Cat6 drop in every bedroom, and managed bulk internet, because high-speed Wi-Fi is one of the first things students ask about. The electrical drawings showed one data outlet per unit and one IDF closet per floor at the center of the building.

Copper runs are limited to about 295 feet from the IDF to the outlet under TIA standards. On a long, L-shaped floor, the units at the far ends were past that from a single central IDF. The IDF as drawn was also too small for the switches, patch panels, and cooling the spec required, and it had no dedicated circuit or HVAC.

Adding a second IDF per floor after framing means taking space from a unit or a corridor closet, plus new conduit and rated wall penetrations. Adding drops after drywall means fishing cable through 650 bedrooms at $150 to $400 per drop. The firm priced it at $100,000 to $300,000 with 2 to 6 weeks of delay. Fixed before permit, it was $2,000 to $5,000.

The fifth was outlets back to back in the demising walls. A-601 specified a 1-hour rated demising wall to a listed UL design that also met the code's STC 50 sound requirement, with resilient channel and two layers of Type X gypsum on one side. The electrical unit plans placed outlets back to back on both sides of those walls in the bedrooms, and the plumbing plans put kitchen sinks on the same walls in mirrored units.

Back-to-back boxes in a rated wall need a minimum horizontal separation, typically 24 inches, or listed putty pads, and plumbing penetrations need listed firestop systems. Back-to-back boxes also undercut the acoustic rating, and noise is the top complaint in student housing. The drawings showed neither the separation nor the protection, and the firestop spec listed systems that did not match the wall's UL design.

That fails above-ceiling and in-wall inspections one unit at a time. Across hundreds of identical unit plans, it means relocating boxes or adding putty pads at thousands of locations, at $25 to $150 each. The firm priced it at $50,000 to $200,000 with 1 to 4 weeks of delay across floors. Fixed before permit, it was $1,000 to $3,000.

See higher education and student housing drawing review, Ohio plan review requirements, mid-rise wood frame coordination, low-voltage coordination, fire-rated assembly coordination, fire and life safety checks, and the Boston campus building review.

$510,000 to $1.7 Million in Field Rework Fixed for $11,000 to $33,000

Helonic flagged all five before the set was issued for permit, while each fix was still a drawing revision.

Fixed at that stage, the five came to $11,000 to $33,000. Found in the field, the firm priced the same five at $510,000 to $1.7 million, before counting the damage from a burst pipe in the garage.

The sprinkler standard carried the largest cost. A bid based on NFPA 13R for a building that needs NFPA 13 would have reached plan review or framing short of attic, concealed space, and balcony coverage across all five residential floors.

The sprinkler standard, the garage freeze protection, and the data drops were all drawings that did not carry what the specs required. Across 1,000+ drawing packages Helonic has reviewed, about 6 in 10 sets with specifications had at least one conflict between the drawings and the project manual. See what Helonic found across 1,000+ drawing reviews.

NFPA 13R Limits, IBC Sound Ratings, and Ohio Freeze Protection on a Podium Building

Ohio buildings are permitted under the Ohio Building Code, which the Ohio Board of Building Standards adopts statewide from the International Building Code. Plumbing follows the Ohio Plumbing Code, based on the International Plumbing Code.

The IBC limits NFPA 13R to Group R buildings of four stories or less above grade plane, with further limits on the height of the top floor and the roof. Past that, the building needs full NFPA 13, which sprinklers attics and combustible concealed spaces unless they are filled with noncombustible insulation. The code analysis put this building past the 13R limits once the podium was counted.

NFPA 13 also requires wet-pipe systems to stay at 40°F or above. An open garage in an Ohio winter cannot, which is why the spec called for a dry-pipe or antifreeze system there, and why domestic water in the same space needs heat trace and insulation.

Walls between dwelling units need an STC rating of 50 under IBC Section 1206, and the same walls are usually 1-hour fire partitions. Electrical boxes are membrane penetrations. The IBC allows them on opposite sides of a rated wall only when they are separated horizontally, typically by 24 inches, or protected with listed putty pads or another listed method.

Van-accessible parking needs 98 inches of vertical clearance along the space, the access aisle, and the vehicular route under the 2010 ADA Standards. Horizontal data cabling is limited to 90 meters, about 295 feet, under TIA-568.

“Our demising walls were rated and acoustically designed, and then the electrical unit plans put outlets back-to-back on them in every bedroom. Helonic found it before we issued for permit. That's one coordination miss that becomes thousands of field fixes in student housing.”

Ohio Student Housing Drawing Review: Questions and Answers