Want to do something constructive around your house this weekend? How about a quick, inexpensive home-improvement project? Simple home maintenance can alleviate the need for large and often costly repairs.

"One of the biggest mistakes that homeowners make is letting small problems turn into big ones," said Kathleen Kuhn, president of HouseMaster. "Home maintenance should not be a mystery. If homeowners follow a simple maintenance checklist on a regular basis, they can keep their home in working order for many years to come."

Here are 25 tips that the home inspection service says homeowners can do for under $25 each, but will save a lot down the road:

1. Seal roof flashings or replace missing roof shingles. This simple weekend project helps avoid the little roof leaks that, over time can create expensive damage to the roof and underlying elements.

2. Extend or install downspouts or splash blocks. Extensions help divert water away from the house, avoiding basement leaks, flooding and soil erosion.

3. Re-grout the bathroom/bathtub tile. Keeping the tiles well-sealed prevents water seepage to the underlying surface, which can lead to costly problems down the road.

4. Regularly change your furnace and air conditioning filter. Clogged filters reduce heating and cooling efficiency and can reduce the useful life of the appliance.

5. Fill in low spots at foundation with soil. Addressing these gaps will help prevent basement leaks and flooding down the road.

6. Clean the gutters. Maintaining a clear path for rain runoff from the roof helps avoid expensive water damage to the house and its structures.

7. Caulk exterior trim, windows and doors. Water easily finds its way into cracks and crevices. Keep it out by sealing all gaps.

8. Apply deck preservative regularly. Avoid premature wear and tear by periodically applying a sealant to protect the wood from the elements.

9. Trim trees near the house and roof. Falling branches and wind-blown limbs can damage the roof and siding. Overhanging branches can be an invitation for wood destroying insects.

10. Clean the kitchen exhaust fan. A grease buildup will tax the fan and increases the potential for a fire.

11. Clean out your clothes dryer vent. Vent ducts clogged with lint reduce drying efficiency and present a fire hazard.

12. Keep an eye out for termite tubes or carpenter ants. A regular, visual check of your home's structure may give you a chance to call in an exterminator before significant damage occurs.

13. Vacuum air duct covers. This simple cleaning can minimize the spread of dirt through the house.

14. Move stored firewood away from the foundation. This reduces the potential of wood destroying insect infestation.

15. Clean sluggish drains. This reduces the potential of leakage, pipe damage or overflow.

16. Check toilet for cracks in bowl or tank cover and verify the toilet is properly secured to the floor.

17. Clean debris from exterior air conditioning unit. Unlike most systems in your home, your central a/c system is generally housed on the exterior of the home. Keep it free of debris at all times so the system is properly vented.

18. Check for proper venting in attic and soffits. Make sure all exterior drains are free and clear of debris and are draining properly. Water that does not drain properly can cause seepage into lower level or basement.

19. Test Ground Fault Circuit Interrupters; special outlets designed to reduce the potential for electrical shock.

20. Seal asphalt driveways. This reduces water related deterioration.

21. Test the auto retract feature of garage doors to ensure they stop/reverse immediately if something blocks their movement.

22. Remove vegetation growing along the foundation. Overgrown vegetation is an invitation to rodents, insects and moisture. In addition large roots can cause pressure on the foundation.

23. Flush out water heater through the drain valve to flush out sediment and allow the gas or oil water heater to operate more efficiently and safely.

24. Check interior and exterior stairs for any possible tripping hazards. Also make sure all handrails are properly secured.

25. Apply deck preservative to wood decks. This reduces potential rot and deterioration.

A construction method for leak-free skylights is detailed in the July issue of Fine Homebuilding.

"I used to worry every time I installed a skylight," writes Mike Guertin in the magazine. "Even with the best installation detailing, I could still expect a storm to hit from just the right direction and drive water behind the flashing. When I discovered peel-and-stick membranes, my worrying days ended. I follow a series of simple steps that hasn't failed in more than 15 years."