Before you approach a house, look at it form a distance. Does the house line up with the others? Do the walls bulge or lean? Does the building look lop-sided? These are all indicators of issues. They could mean the foundation should be examined or that there is work needed on the structure, but you should make a note of these facts.
I went over signs of foundation concerns above, so I want to focus on other parts of the home. Walking around the property, I look for standing water or dips in the grading. I also look to see if the grading will allow the water to flow freely to the street. Water causes damage to the foundation and siding of a home, so I look for the ways it could leave the area. Thinking about water, I look towards the roof for gutters. It is not a cause for alarm if a building does not have them, but gutters do effectively transport water away from the house, when installed correctly. The gutters should be well attached, and there should be no debris in them. The downspouts should not be damaged (gardening efforts seem to cause problems). There should be a splash guard or tube to direct the water further away from the building, once it has left the downspout. A pet peeve of mine, but not technically a problem, are downspouts placed on the path leading to the front door. Builders point out that this is a perfect path to have water move away from the house. I think about the fact that some one will be walking through that water during a good rain.
Since we are looking at grading, we will move into the bushes. (Yes, neighbors do look at me curiously when inspecting a home, but if I see them, I try to talk to them, so that they know I am not a threat, and I may obtain some information on the house). Mulch is great for plants, but we seldom judge the effect it has on our siding. When the house is clad in a wood material, there should be six inches between the siding and the ground. For a material like brick or concrete block or plank, six inches between the ground and siding is acceptable. Moving up from the grading, we can look at the plants in the yard. Roots, branches, and leaves can all be combatants against a home.
A typical American home does not posses enough yard space for a large tree, but I would not do without my trees. The basic rule of thumb is that the tree should be spaced away from the home by a measurement equal to its height at full growth. A good average number is forty feet for large trees; twenty to fifteen feet for smaller trees; and five to six feet for good sized bushes. These numbers are never accomplished on the majority of homes. Next best thing is to prevent contact of all branches with the roof and siding. The movement of branches in a strong window will cause serious damage over time.
Do not let leaves pile up on the roof or against the building.Leaves retain moisture, and they make a great home for insects. Both facts will do damage to the home. Roots grow were they get water, so if you prune the branches to be clear of the building, the water from the leaves will drip down there, and the roots will stay in that area. The section on the roof above goes into what to look for on top, so let us go just below the roof to the trim there. For all trim, you will want to look that it is not rotting or damaged.
Keeping your tools simple, I suggest carrying at least a flat head screwdriver.Most items that you need to open will probably have a screw that can be undone with this screwdriver, and the tool can be used for two other functions: a minor crowbar; and a probe. Pushing the screwdriver gently into the trim, you should feel resistance. If the screwdriver can move into the wood, the trim should be replaced. Now look where the trim meets the siding. This fact applies for where two walls join too. There should be no access point for water to get behind the siding. Joints like this should be caulked. Rain can travel sideways (hurricanes and good gusts of wind ensure this), so take a considerate look at these areas. Moisture and water will get behind your siding though, so the next place to look is at how the water will exit.
For brick siding, there will be small holes in the mortar around every three feet.For stucco and EIFS (architectural foam, which looks like stucco), there should be a mesh screen at the bottom. Wood and aluminum siding are designed in such a way that there is a space for water to drain.
Stucco and EIFS will be your big worries.These materials can trap water behind them, and installers have not always been aware of how to properly install a means for letting that water drain out. The situation with this siding is getting better, but these materials are meant for dry climates.
I mentioned attic ventilation in a section above, so now is the time for you to check for these vents in the soffit. Homes built from around 1960 to 2000 will have vents mainly towards the back and sides, and it is not always sufficient. Before 1960, homes may not have had any type of ventilation. Apply lessons from the “Electrical” portion above for examining outside service panels, fixtures and cabling. The “Window” section applies at this time too. Hose bibs (the exterior faucets) should have an anti-siphon device on them. This looks like a metal sleeve over your normal hose connection. It prevents water from the exterior moving up the hose into the drinking water. If you read the sections above, you should have a good idea what to look for on exterior components, so now you can go ring the doorbell. No one home? That is alright. Checking for a functioning doorbell was the last step in the exterior evaluation.