The formula. To determine the lead safe housing requirements that apply to a particular rehabilitation project, you need to calculate the level of assistance. The level of assistance is the lower of:

• Per unit rehabilitation hard costs
• Per unit Federal Assistance

Some Definitions. To understand these terms, it helps to know the following definitions:

• Rehabilitation Hard Costs. The rehabilitation costs are calculated using only hard costs (e.g., physical improvements, utility connections, repairs and replacements, and energy-related improvements). They do not include soft costs or other such costs (e.g., financing fees, relocation costs, acquisition, or administrative costs), nor do they include the costs of lead hazard evaluation and reduction, as described below.
  
  Note that it may be difficult to determine if a hard cost is a rehabilitation cost or a lead hazard reduction cost. For more help on this question, see Is This Rehabilitation or Lead Hazard Reduction?.
  
  
• Lead Hazard Evaluation and Reduction Costs. Lead hazard evaluation and reduction costs include costs associated with site preparation, occupant protection, relocation, interim controls, abatement, clearance, and waste handling attributable to lead-based paint hazard reduction.
  
  
• Federal Assistance. The Federal assistance includes all Federal funds provided to the rehabilitation project, regardless of whether the funds are used for acquisition, construction, soft costs, or other purposes. This also includes funds for program income, but excludes low-income housing tax credit funds (LIHTC), Department of Energy Weatherization Program funds, or non-Federal HOME Program match funds.

Doing the calculation. For single-family projects, this formula is easy—simply compare federal dollars to rehabilitation hard costs. However, in multifamily projects, an additional formula is needed to allocate the cost of common areas and other shared resources.

This formula is: A/AU + B/TU

Where:

A =	Rehabilitation hard costs for all assisted dwelling units (not including common/exterior areas)
AU =	Number of federallyassisted units in the project
B =	Rehabilitation hard costs for common areas and exterior surfaces
TU =	Total number of units in the project

For help doing these calculations, use these examples to help determine the level of assistance for single family units, multifamily properties with all federally assisted units, and for multifamily properties with both federally assisted and non-assisted units.