Over time, metal factory roofs often suffer from water leaks, which can seriously affect production, equipment, and worker safety. To prevent factory roof leaks effectively, it’s essential to identify the root causes and choose the right solution based on the level of damage. In this article, BMB Steel shares over 10 safe, effective, easy-to-apply methods to help you fix leaks, reduce maintenance costs and extend the lifespan of your factory roof.
To select a durable and effective solution to prevent factory roof leaks, the most important step is to clearly identify the root causes of water seepage. Understanding the problem accurately will allow for proper repair and help prevent recurring leaks that could disrupt production. Below are some common causes:
Corrosion at screw points on the metal roof
Metal roofs are constantly exposed to harsh weather conditions. As a result, screw points may become corroded or cracked, creating gaps that allow rainwater to seep through.
Inefficient drainage system
An inefficient drainage system, such as undersized gutters, clogged pipes, improper slopes, can prevent rainwater from draining properly, leading to water accumulation and potential leaks.
Exposure to industrial environments
Factory environments often involve corrosive chemicals, steam, and mechanical impact during production. These factors can accelerate the deterioration of walls, floors, roofs, making them prone to cracks and water seepage.
Initial construction errors
Some leaks may be caused by mistakes during the initial construction phase, such as poorly applied primer, waterproofing layers, incomplete plastering, improper treatment of joints.
Lack of timely repairs
If previous leaks are not thoroughly repaired, the damage can worsen over time. Once the protective surface is compromised, rainwater can penetrate deeper into the structure.
Intrusion of plant roots
Roots or moss growing on the roof can puncture waterproofing layers, allowing rainwater to leak into the building at multiple points.
Poor installation of additional equipment
Installing extra equipment like solar panels, water tanks, etc. without proper techniques can compromise the structural integrity of the metal roof, create holes or weak points that eventually lead to water leakages.
In the peak of the rainy season, heavy and unexpected rains frequently occur. That’s why it’s important to inspect your factory's metal roof early to detect any damage in time. Below are 2 simple methods you can try:
Visual inspection
On dry days, you can climb onto the metal roof and visually examine it for signs of damage, such as rust, corrosion, rotting panels, visible cracks and gaps at the joints, etc. Mark any suspicious areas that might leak, so you can return for a more thorough inspection or perform timely repairs.
Water spray test
Another effective method is to use a water hose to spray directly onto the roof, simulating actual rain conditions. Start by placing the hose at the highest point of the roof to allow water to flow evenly across the surface. Then observe from underneath to detect any leakage or dripping. Mark each leaking spot to prioritize repairs in order of severity.
Safety tips when inspecting a metal roof
Damage level: Minor
Durability: Over 1 year
DIY capability: Can be done yourself
Benefits:
Construction guide:
Damage level: Minor to moderate
Durability: 2-3 years
DIY capability: Can be done yourself
Benefits: Combine waterproofing and thermal insulation, effectively reduce heat, forms a protective barrier.
Construction guide:
Damage Level: Moderate to severe
Durability: 3-5 years
DIY Capability: Should hire a professional
Benefits:
Construction guide:
Damage level: Moderate
Durability: 3-5 years
DIY capability: Requires experienced personnel
Advantages:
Construction guide:
Note: Always wear gloves and safety gear during application. If adhesive gets into the eyes or onto sensitive areas, rinse immediately with water and seek medical attention.
Damage level: Moderate to severe
Durability: 2-3 years
DIY capability: Requires skill or professional assistance
Benefits:
Construction guide:
Note: When using asphalt sheets, ensure they are applied smoothly without wrinkles. Overlap the sheet edges by 10-15 cm, and extend the sheet 15 cm up the wall where applicable. Reinforce weak points such as wall bases, pipe collars, expansion joints with a layer of asphalt primer.
Damage level: Minor
Durability: 6 months to 1 year
DIY capability: Can be done by yourself
Construction guide:
Damage level: Minor
Durability: 6 months to 1 year
DIY capability: Easy to do
Screws used for metal roofing typically come with rubber washers to provide sealing and stability. Over time, rainwater can cause them to rust and loosen.
Construction guide:
Note: Replace screws one at a time to avoid roof misalignment during strong winds.
Damage level: Moderate to severe
Durability: 2 years or more
DIY capability: Requires a professional
Construction guide:
Damage level: Moderate to severe
Durability: 3 years or more
DIY capability: Requires a professional
Construction guide:
Damage level: Moderate
Durability: 2-3 years
DIY capability: Requires a professional
Construction guide:
Damage level: Mild to moderate
Durability: 3-5 years
DIY capability: Can be done yourself
Metal roofs exposed to acid rain, harsh sunlight and UV rays tend to deteriorate. These factors degrade the protective layer, leading to oxidation, corrosion and eventually holes.
Construction guide:
You can easily purchase various types of leak-sealing adhesives at construction material stores, hardware stores, or order online via e-commerce platforms such as Shopee, Tiki, Lazada.
Product name |
Unit price (VND) |
Selleys Silicone Blockade leak sealant |
125.000 – 150.000/360g tube |
X’traseal MC-201 leak sealant |
Approx. 43.000/tube |
Heat-resistant Silicon Sealant Selsil RTV |
Approx. 110.000/310ml tube |
Acrylic roof leak sealant |
Approx. 52.000/can |
Polyurethane roof leak sealant |
Approx. 2.850.000/20kg bucket |
TX 911 waterproof sealant |
70.000 – 96.000 |
AS – 4001SG roof waterproof sealant |
250.000 |
Neomax 820 roof leak sealant |
1.050.000/5kg set |
Note: Sellers often provide direct usage advice. You can also refer to the instructions on the product packaging to ensure proper application.
If you choose to hire a professional contractor for industrial metal roof leak repairs, below is a reference price list:
Work item |
Unit price (VND/m2) |
Crack, joint treatment on metal roofs |
140.000 |
Leak repair using Sika |
120.000 – 160.000 |
Leak repair using tiling |
400.000 – 500.000 |
Leak repair using asphalt |
120.000 |
Leak repair using waterproof paint |
80.000 |
Leak repair using hot bitumen membrane |
220.000 |
Metal roof area (m2) |
Unit price (VNĐ) |
Less than 500 m2 |
25.000 |
500 m2 – 1000 m2 |
20.000 |
1000 m2 – 2000 m2 |
16.000 |
Over 2000 m2 |
13.000 |
Waterproofing costs will depend on several factors, such as the construction method, materials used, the size of the leak area, actual damage level, etc. The contractor will carry out an on-site inspection and provide a detailed quote after agreeing on the repair solution.
In general, the cost of metal roof leak repair is usually lower than other structural repairs. The process is also relatively quick, so you should address any issues early to avoid higher costs later.
Repairing and waterproofing metal roofs in factories protects your assets, ensures production safety, and helps save on long-term repair costs. Depending on the specific level of damage, you can choose a simple DIY solution or hire a professional contractor to ensure durability and proper technical execution. Don’t wait until the roof is severely leaking, conduct regular inspections and maintenance to maximize the performance and lifespan of your facility. If you're planning to build a steel structure factory or industrial facility, BMB Steel is ready to support you with effective, tailored solutions today.