Knowledge Base · Choosing a Roof
Are Interlocking Roof Tiles Better Than Overlapping Shingles?
For most New England roofs, yes: interlocking roofing generally resists wind and driven rain better than overlapping shingles, because every piece is held by its neighbors and the fasteners are covered. The material still matters. Interlocking aluminum panels add rust resistance and light weight, while heavy interlocking concrete or clay tiles can overload older framing and crack in hard freezes.
Technically reviewed by Scott Plumptree, Director of Marketing · Updated 2026-10-07
At a glance
- Overlapping shingles rely on gravity, nails and sealant; interlocking pieces are held on several sides.
- Locked edges give wind nothing to lift and give sideways rain a harder path in.
- Material matters: aluminum interlocking panels are light and don't rust.
- Heavy concrete or clay tile needs strong framing and can crack with freeze–thaw.
- Flashing at chimneys, skylights and valleys decides leak performance on any roof.
What is the difference between interlocking and overlapping roofing?
The difference is how each piece is held in place. Overlapping roofing, such as asphalt or wood shingles, is laid in courses where each row sits on top of the one below. The pieces are nailed near the top and rely on gravity, adhesive strips and the overlap itself to keep water out. Interlocking roofing uses pieces with formed edges that hook into the surrounding pieces. On Interlock® aluminum shingles, the lock runs on all four sides: the panel is fastened along its top flange, locks over the course below, and engages the panels beside it. The next course covers the fasteners. Instead of hundreds of separate shingles, you end up with one connected surface that moves and sheds water as a unit.
Are interlocking roofs better in high wind?
Yes, interlocking roofs generally handle wind better because wind damage starts at loose edges, and an interlocking roof has none. On overlapping shingles, gusts work under a tab, break the seal and peel it back, and once one piece goes, the ones above it are exposed. New England sees this every storm season, from coastal nor'easters along the South Shore and Rhode Island to strong winds on exposed hilltops in Vermont and New Hampshire. Interlock® aluminum shingles are rated for winds up to 120 mph when installed to manufacturer specification. That condition is the honest part of the claim: the starter course, fastening pattern and edge trim all have to be right for the rating to apply.
Do interlocking roofs leak less than overlapping shingles?
Interlocking roofs are less prone to leaks in the field of the roof, because the joints are formed channels rather than simple laps and the fasteners are covered. Wind-driven rain that is pushed up and sideways under an asphalt tab has a much harder time getting through a locked metal joint. On any roof, though, most leaks start at the details, not the open surface. Chimneys, skylights, valleys, sidewalls and plumbing vents are where water finds its way in if the flashing is poorly done. That is true for asphalt, slate and metal alike. When you compare roofs, ask how each contractor handles those details, because that answer will predict your leak risk better than the shingle type alone.
Are all interlocking roof tiles a good choice for New England?
Not all of them. Interlocking concrete and clay tiles exist too, and they bring two concerns in this region. The first is weight. Tile is heavy, and many New England Colonials, Capes, triple-deckers and farmhouses have rafters that were never built for it, especially with a heavy snow load added on top. Adding tile can mean structural work. The second is freeze–thaw. Masonry and clay products can absorb some water, and repeated freezing can crack or spall them over time. Interlocking aluminum avoids both problems. At roughly 0.4 to 0.7 lb per square foot, it is far lighter, it does not absorb water, and it does not rust in coastal salt air. Interlock® offers a Mediterranean Tile profile for owners who want the tile look without the tile weight.
Which lasts longer and is easier to repair?
A well-installed interlocking aluminum roof usually lasts longer than an overlapping asphalt roof, and it is backed in writing. Interlock® panels carry the Guardian Lifetime Limited Material Warranty for the original purchaser while they own the home, transferable once with the second owner covered to 50 years from substantial completion, plus a 30 Year Alunar® coating warranty on the finish. Repairs are a different skill. An asphalt shingle can be slipped out and replaced by most roofers. An interlocking panel can also be replaced individually, but the surrounding panels have to be released carefully, so it is a job for the installer's trained crew. The trade-off is that interlocking roofs need repairs far less often, since there are no tabs to blow off or granules to wear away.
When might overlapping shingles still make sense?
Overlapping asphalt shingles can still make sense when budget is the main concern or when you expect to sell soon. They cost less to install, almost any roofer can work on them, and many neighborhoods are full of them. They also make sense where an interlocking product can't go. Interlock® shingles need a pitch of at least 3/12, so very low-slope sections need another system regardless. If you are weighing the two, think about how long you will own the home, how exposed it is to wind and salt, how old the framing is, and how many times you are willing to replace the roof. In a historic district, also check with your local historic district commission, which may have views on any change of material.
Common questions
Is an interlocking metal roof better than asphalt for nor'easters?
In wind and wind-driven rain, generally yes. Locked edges leave nothing for gusts to lift, and covered fasteners keep holes out of the weather. Interlock® shingles are rated to 120 mph when installed to manufacturer specification. Flashing quality still decides how any roof performs at chimneys and valleys.
Are interlocking clay or concrete tiles good in cold climates?
They can be used, but they are heavy and can be affected by repeated freezing and thawing. Many older New England houses would need structural review before carrying tile. Interlocking aluminum gives a similar look at a fraction of the weight.
Can interlocking panels be installed over existing shingles?
Sometimes. A single layer of asphalt may stay if an inspection finds it suitable. Cedar shingles, cedar shakes, concrete tile and natural slate are always removed first, and any rotted decking is replaced before the new roof goes on.
Do interlocking roofs stop ice dams?
No roof stops ice dams by itself. They form when attic heat melts snow that refreezes at the eaves, so the solution is air sealing, insulation and ventilation. Ice damming is excluded from the Interlock® material warranty.
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