A somewhat gray area, probably with no, one, absolute answer that fits all applications.
The cost differential of special materials or mods. specifically designed and required to meet the requirements of the solar equipment to make it function as designed over the cost of other similar materials but without the solar consideration requirements might be a starting point.
A possible example: The cost of beefing up an old, flat roof, material, labor and engineering to be able to accept a new, larger loadings from a ballasted, saw tooth array might be something the IRS would sign off on. Or, I suppose they might get porky and disallow some of that extra cost - such as the portion of the improvement that would bring and old design up to current building code requirements without the added beef that the solar requirements add to the mod.
I'd guess every situation is different. Talk to your accountant and have the accountant talk to your engineer. Believe it or not, a call to the IRS is not out of the question. At least, if such a call were to be made and documented, that it was made might help your cause in an audit (provided I suppose, you can show you made the best effort at conformance to what was suggested, or that what you were told was senseless).
The cost differential of special materials or mods. specifically designed and required to meet the requirements of the solar equipment to make it function as designed over the cost of other similar materials but without the solar consideration requirements might be a starting point.
A possible example: The cost of beefing up an old, flat roof, material, labor and engineering to be able to accept a new, larger loadings from a ballasted, saw tooth array might be something the IRS would sign off on. Or, I suppose they might get porky and disallow some of that extra cost - such as the portion of the improvement that would bring and old design up to current building code requirements without the added beef that the solar requirements add to the mod.
I'd guess every situation is different. Talk to your accountant and have the accountant talk to your engineer. Believe it or not, a call to the IRS is not out of the question. At least, if such a call were to be made and documented, that it was made might help your cause in an audit (provided I suppose, you can show you made the best effort at conformance to what was suggested, or that what you were told was senseless).
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