SOLUTIONS LIBRARY

FROST PREVENTION - INSTITUTION

Challenge

 

To provide flame-free heating applications in sequence with the phases of winter construction of a building which included

1.      At excavation phase – prevent frost build-up prior to concrete pours

2.      At concrete-pour phase – provide concrete cure temperatures

3.      At structure phase (walls and roof) – provide interior heat for construction and drying

4.      Post construction phase – provide heat to resist ground-frost intrusion until Spring arrives  

 

Objective

 

·        Design and install flexible systems which perform stand-alone applications or simultaneously

·        To provide systems which operate on a variety of fuel systems – as available on site.

 

Solution

 

·        Heat the ground prior to and after concrete pours to combat frost – eventually abandon hoses. 

·        After excavation and prior to pouring of footings and slabs, a designed zone-system utilizing line heat exchangers was laid beneath the building footprint – with a dedicated Central Heating Unit (CHU) to pump heated glycol through the hoses. The hose-system was meant to be abandoned after the engineers were satisfied that ground frost would no longer be a threat to the structure.

·        Provide heat for concrete cure / building heat / drying

 

A designed system of CHU’s provided flame-free hydronically delivered heat to:

1.      Cure poured concrete elements (footings, slabs, walls) with line heat exchangers and fan coils.

2.      Provide building heat via fan coils to provide a warm environment for construction crews.

3.      Provide a drying process so finishing crews could install drywall, carpets etc.

 

Result

 

·        The project was successfully completed – to the satisfaction of the Contractor

·        Flame-free heat was provided through-out all phases with no toxic combustion gases in the interior of the building, and no carbonization in any of the concrete curing applications.

·        Drying and moisture extraction was efficient

·        Frost build-up was completely eliminated through all phases of construction

·        Fuel costs were lower than open-flame alternatives, due to operating efficiencies of the hydronic systems.

·        Initial fuel systems were propane – converted to natural gas as it became available on site.