A capillary gap is a very narrow space or tube in a material, capable of attracting liquids (usually water) through capillary forces. In construction, this concept refers mainly to pores and microseals in building materials such as brick, concrete or stone, which can absorb and transport water. Capillary gaps can affect insulation properties, durability and strength of materials, as well as provide a way for pets, salts or chemicals, leading to material degradation. In construction, measures are often taken to minimize the negative impact of water penetrating capillary gaps, using impregnates or special material mixtures.