Another common cause is poor water management<\/strong>. Soil that remains moist for a long time loses its stability. If the driveway is not well drained, water seeps under the asphalt, weakening the base and creating compression points that, along with freeze-thaw cycles, lead to subsidence. <\/p>\n\n Finally, subsidence can sometimes appear over buried services<\/strong>, such as water or gas pipes. If the backfill in these trenches has not been properly compacted before the asphalt is laid, the soil will gradually subside below the surface, even several years after the work. <\/p>\n\n To prevent subsidence, it all starts with excavation<\/strong>. Loose or organic soil (black soil, soft clay, roots) should be removed until a stable soil layer is reached. The depth of excavation varies depending on the bearing capacity of the land, but it is usually at least 12 to 18 inches. This layer is then replaced by a bed of gravel or clean stone, divided into several layers compacted one by one. <\/p>\n\n Compaction<\/strong> is essential at every stage. It must be carried out using vibratory rollers or mechanical plates, never by hand or approximately. A well-compacted foundation provides a flat, dense surface on which asphalt can be applied without the risk of differential movement. <\/p>\n\n It is also recommended to use a geotextile<\/strong> between the natural soil and the foundation to prevent the migration of fine particles and limit the development of areas of weakness. It also prevents plants from piercing the siding over time. <\/p>\n\n Good drainage is essential to prevent water from accumulating under the entrance. It is important to make sure that the slope of the land directs the water towards the street or ditches, never towards the house or in low areas where it could stagnate. A minimum slope of 2% is recommended along the length of the parking lot. <\/p>\n\n In some cases, it may be necessary to install a linear drain<\/strong>, especially if the land is in a basin or bordered by low walls. This type of drain captures surface water and redirects it to a drainage system. <\/p>\n\n Concrete or paving stone curbs, often used for aesthetic reasons, should also be installed in a way that does not block runoff. They must follow the natural slope of the land and never form basins. <\/p>\n\n Finally, around the house, it is important to check that the downspouts do not send water directly under the inlet. Extension cords or underground conduits can be installed to direct water away from the paved area. <\/p>\n\n Even with an impeccable base, the asphalt must be laid with care. The bituminous mixture must be delivered at the right temperature so that it can be spread and compacted properly. If it is too cold, it does not adhere well to the surface and may crack prematurely. <\/p>\n\n The thickness of the coating is also crucial. A layer that is too thin does not withstand mechanical stress, while a layer that is too thick can trap moisture. In general, for a residential driveway, a thickness of 2.5 to 3 inches after compaction is ideal. <\/p>\n\n Compaction of the asphalt layer must be done within minutes of application. Any delay can lead to uneven compaction and the appearance of air pockets. It is in these pockets that water and frost will do their work, weakening the structure and eventually causing hollows. <\/p>\n\n Once the entrance is complete, its maintenance plays a crucial role. It is advisable to wait a few days before parking there, the time it takes for the asphalt to harden completely. You should also avoid always parking in the same place, especially in the first few weeks. <\/p>\n\n Over time, applying a protective sealant<\/strong> every 2 to 3 years helps preserve the elasticity of the bitumen, prevent water infiltration and slow oxidation caused by the sun and de-icing products.<\/p>\n\n You should also watch the curbs and joints, especially where the asphalt meets the concrete of the garage or sidewalks. A crack in this area can allow water to pass through and weaken the foundation laterally. In the event of a crack, a quick sealing with a suitable product prevents it from getting worse. <\/p>\n\n Finally, quickly removing leaves, snow or ice that could trap moisture extends the life of the structure. Standing water is always the enemy of asphalt. <\/p>\n\n Avoiding subsidence in an asphalt driveway is not a matter of luck: it is the result of rigorous planning, precise execution and minimal but regular maintenance. Every step \u2013 from excavation to drainage, compaction and installation \u2013 must follow the rules of the art to ensure a flat and stable surface for years to come. <\/p>\n\n On the North Shore and in the western areas of the island of Montreal, calling on an experienced company is the best guarantee of a sagging-free result. Bucaro Contractors Inc.<\/strong>, active for more than 60 years in the field of residential paving, masters the entire process with particular attention to the quality of the subsoil and water management. By opting for their services, you benefit from local know-how adapted to the climatic realities of Quebec, and you ensure a durable, aesthetic entrance without unpleasant surprises. <\/p>\n\n <\/p>\n","protected":false},"excerpt":{"rendered":" Nothing is more frustrating for a homeowner than to notice, a few months or years after the installation of their asphalt driveway, the appearance of hollows, undulations or sagging areas. These sagging effects affect aesthetics, compromise drainage, and can damage vehicles over time. In many cases, they are not due to natural wear and tear, […]<\/p>\n","protected":false},"author":4,"featured_media":2118,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"yasr_overall_rating":0,"yasr_post_is_review":"","yasr_auto_insert_disabled":"","yasr_review_type":"","footnotes":""},"categories":[20,24],"tags":[],"class_list":["post-2123","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-paving-and-asphalt","category-techniques-and-innovations-in-paving"],"acf":[],"yoast_head":"\n![\"\"](\"https:\/\/bucaro.ca\/wp-content\/uploads\/2025\/04\/Depositphotos_380988172_S.jpg\")
<\/figure>\n\nA well-designed foundation: the first line of defence<\/h2>\n\n
Drainage: an often overlooked determining factor<\/h2>\n\n
![\"\"](\"https:\/\/bucaro.ca\/wp-content\/uploads\/2025\/04\/Capture-1024x561.jpg\")
<\/figure>\n\nAsphalt laying: precision, temperature and timing<\/h2>\n\n
The right maintenance habits to prevent sagging<\/h2>\n\n
Conclusion: Stable Entry Relies on Expert Execution<\/h2>\n\n