Get moving now, if you intend to remodel your house this summer. It's later -- much later -- than you think.

Lower interest rates have spurred thousands of house-proud families to add the sunroom or the kitchen they've been dreaming of for years. Some building contractors already are booked into autumn.

At banks and S&Ls, the flood of home-refinancing applications is tying up all the appraisers. So if your home-improvement loan is large enough to require that the house be appraised, it might take three weeks or more to get your money. Otherwise, the loan should go through within 10 days to two weeks.

Lenders prefer that you use an experienced contractor. They turn their coldest eye on borrowers who want to do a major remodeling job themselves. If you do it poorly, under budget or are unable to finish, the bank has a problem on its hands.

To get a loan for a big do-it-yourself project, show the lender your plans and cost estimates, and summarize your building experience right in the loan application. Smaller projects shouldn't be a problem.

Lenders often suggest that you buy extra life and disability insurance to repay the home-improvement loan in case you die or become too ill to work.

But the bank's policy is often the most expensive one around, per $1,000 of coverage. If you want extra insurance, compare the bank's rates with a cheap term policy bought through your life-insurance agent.

Almost any home-improvement loan will be secured by a mortgage against your house. Counting your first mortgage, plus any additional loans, you can usually get 80 percent of the value of the house (assuming that your income is high enough to carry the cost).

Some lenders figure the 80 percent against the likely value of your expanded or remodeled house, which gives you extra borrowing power. But don't expect to get back the full amount you spent, when you put the property up for sale. Used houses (and rooms) almost always go for less than the same thing new. Five financing ideas: If you are going to refinance your house anyway, in order to get a lower mortgage payment, the cheapest way to raise home-improvement money is to take a larger loan and use the extra money for the work you want to do. The national average on 30-year fixed-rate mortgages is now 10.4 percent, according to the Bank Rate Monitor, and 8.4 percent on adjustable loans. A second mortgage is quicker and easier to get than a full refinancing, and the closing costs should be lower. Repayment terms usually last as long as 15 years, at interest rates 1 to 2 percentage points higher than those on first mortgages. Home-improvement loans are another form of second mortgage and generally cost about the same. Current interest rates at Buffalo-based Goldome Federal Savings Bank, one of the nation's largest home-improvement lenders: 12.5 to 13.25 percent on fixed-rate loans and 10.5 percent on adjustables. Home-equity loans provide a revolving line of credit on the difference between your first mortgage and as much as 80 percent of your home's value. They may cost from $800 to $1,300 to set up. Rates float 1.25 to 2.5 points above the prime business lending rate, for a current cost of about 9.75 to 11 percent.

This form of borrowing is especially useful for home improvements because you don't have to borrow and pay interest on all the money at once. Instead, you borrow as needed to pay the bills. Many large remodeling companies offer their own financing. "But it would be very unusual if a borrower couldn't get a better rate elsewhere," Wayne Bengston of the U.S. League of Savings Associations told my associate, Virginia Wilson.

Warning: Where the real estate market is bad -- for example, in Houston -- it's hard to find any home-improvement money at all. Houston's United Savings was once the top lender in the country. Now it gives no second mortgages at all, according to spokeswoman Diane Olson, because of the risk that falling house prices will make it hard to recover the loan.