Why vinyl siding cracks
Vinyl is a plastic (PVC), and it ages. Cold makes it brittle, UV exposure fades and weakens it over the years, and a hard impact from hail, a branch, a ball or a mower can crack it in a second. Panels nailed too tightly cannot move when the temperature changes, so they split along the nail slots. Seeing which of these caused the crack tells you whether one repair will do or the whole wall is aging out.
Repair or replace: what to do with each type of damage
| Damage | Repair | Replace |
|---|---|---|
| Hairline surface crack | Seal with matched sealant as a short-term fix | If it keeps growing |
| Crack running through a panel | Not recommended | Replace that piece |
| Split along nail slots | Re-nail loosely if intact | If it split between slots |
| Cracked or loose corner post | Re-secure if straight | Replace if cracked or pulled away |
| Warped or wavy panel | Fix the cause, re-seat | If it will not lay flat |
For the how-to behind a replacement, see StormGuard Siding's guide to replacing a piece of vinyl siding.
Fixing damaged vinyl siding corners
Outside corner posts take the most abuse: they get bumped, they hold the ends of every course, and they are where wind gets in first. A corner post that is only loose can be re-nailed through its slots. One that is cracked, bent or pulled away needs to be removed, which means the panels meeting it must be unlocked and their ends slid out, so that is often a job for two people or a pro.
Why vinyl siding warps, and the fix
Warping comes from heat. Common causes are reflective low-E windows throwing sunlight at a neighboring wall, a gas grill left near the siding, dark replacement paint, and nails driven tight so the panel buckles instead of sliding. Move the heat source, let the panel cool, and unlock it and re-nail it loosely. If it stays wavy, replace it. Do not use a heat gun or paint dark colors on it.
What the Chesapeake climate does to vinyl
Annapolis swings from humid summer heat to freezing winter nights, so vinyl expands and contracts through a wide range every year. Waterfront wind from the storms that roll up the bay finds weak edges, and older homes in Hillsmere Shores often show the cumulative result: many small cracks, loose panels and faded sun-side walls.
When it is time to call
If you see more than a handful of cracked panels, if a crack has exposed sheathing, or if the wall behind feels soft, call StormGuard Siding. A few pieces is a repair; widespread brittleness may mean the wall is nearing replacement, and StormGuard Siding's guide to repair versus replacement in Maryland will help you decide. For urgent damage, use StormGuard Siding's emergency vinyl siding repair line.
Frequently asked questions
Can cracked vinyl siding be fixed with glue or tape?
Not for long. A crack in a panel keeps flexing with temperature, so glue and tape peel or reopen. Replace the piece.
How do you fix a crack in vinyl siding temporarily?
A color-matched exterior sealant can close a hairline crack for a while, which is useful before a storm. Plan on a real repair soon after.
What causes vinyl siding to buckle or warp?
Most often heat reflected from low-E windows or a grill, or nails driven too tight so the panel cannot slide as it expands.
Is cracked siding a sign I need a new roof or gutters?
Not usually, but water running down a wall from failed gutters can damage the siding and the wall behind it. Check both when you inspect.
Keep reading
- How to Replace a Piece of Vinyl Siding Step by Step
- How to Fix a Hole in Vinyl Siding (Small to Large)
- Emergency storm damage siding repair
- How to Fix Chipped Vinyl Siding from a Mower or Rock
- Common Causes of Siding Damage (and How to Prevent Them)
Need hands-on help? StormGuard Siding provides emergency siding repair in Annapolis, MD, and the neighborhoods the technicians cover are listed on StormGuard Siding's service areas page. Quick answers are on StormGuard Siding's FAQs page.