You cannot deduct general repairs to the residence just because you have an office in home. The only deductible repairs relate directly to the business. Only the portion of heat light and water and repairs that directly relate to the business area can be claimed. You can replace the flooring in the office, add more lighting, put in shelves, etc. All of those items are claimable. The roof over the whole house can't be claimed, or the chimney, or the fence as a deduction of the business.
You really do not want to add your residence as a business asset, as when you sell it, you would be paying much higher capital gains on a larger portion of revenue property. Also, if you closed the business, you would have a tax liability due to a change of use from a revenue property back to a personal residence.
