Self-clinging climbers such as Boston ivy and Virginia creeper (Parthenocissus sp.) do not usually cause damage to wall surfaces, but common or English ivy (Hedera helix sp.) supports itself by aerial roots and where these penetrate cracks or joints they may cause structural damage. Sound masonry is unaffected.
Its dense cover can hide defects in the fabric of the building and hinder maintenance work. Ivy may also provide access for intruders and harbour pests such as mice.
Where brickwork is sound, the main problem is to keep growth away from gutters and paint work.
It has been suggested that vegetation attached to walls could lead to dampness resulting from slower drying conditions following rain. This may be plausible on a south-west facing wall where the rain is driven by prevailing winds. However, other sources suggest that such plants will have a slight drying effect on mortar and will also provide some degree of insulation in winter, particularly evergreen ivies covering exposed north and east-facing walls.
Large climbers can pose a risk to buildings. Such problems are most likely with older property, those with shallow foundations and those built on clay soils.