Slate roofs at home: are they dangerous and what should you do?

Grey corrugated asbestos-cement (“slate”) roofing sheets cover the roofs of many Latvian houses, sheds and saunas, and they almost certainly contain asbestos. As long as the sheets are intact and nobody disturbs them, they pose no significant risk to health. The risk arises when slate is broken, sawn, drilled or sanded, or when it starts to crumble of its own accord.^[1]

How to recognise asbestos slate

Slate is asbestos cement: a Portland cement mortar in which asbestos fibres act as reinforcement. In Latvia it was produced in Riga from 1935 and in Brocēni from 1938, and every 1,000 sheets used around 1,250 kg of cement and 124 kg of asbestos.^[3]

• Appearance: grey corrugated or flat sheets. Asbestos-containing materials are most often greyish with a fibrous structure, and become friable when damaged.^[5]
• Age: if the roof was laid before 2002, assume it contains asbestos. In Latvia, Cabinet Regulation No. 158 of 25 April 2000 banned the use and sale of asbestos and asbestos-containing materials from 1 January 2001; even so, at least 1,380 t of asbestos was still imported in 2001.^[6] The use of asbestos has been banned throughout the EU since 2005.^[4]
• At a break, fine fibres are often visible. Do not tear or break sheets to check this!
• If in doubt: a sample can be sent to an accredited laboratory. Take the sample from material that is already damaged, then seal the damaged spot with water, a sealing solution or adhesive.^[7][5]

Slate is not the only place in a house where asbestos may be found. See “Where asbestos hides in a house”.

Is my roof dangerous?

Asbestos is dangerous when its fibres are inhaled.^[4] Intact slate that nobody disturbs releases no significant amount of fibres.^[1] Over time, however, weathering wears the material down and it crumbles, gradually releasing harmful substances.^[8]

If you are replacing your roof

The safest option is to entrust the work to a company. Since December 2025, a company needs a permit from the State Labour Inspectorate (VDI) to remove asbestos-containing materials, and the VDI publishes a list of permit holders on its website.^[10] Before signing a contract, check that the firm is on this list (vdi.gov.lv).

If you do remove the roof yourself, follow these steps:

1. Protection. Disposable overalls, gloves, a P3 respirator and footwear that can be washed.^[11] An ordinary dust mask or medical mask does not protect you.
2. Prepare the site. Close windows and doors, keep children and pets well away from the work area, and spread plastic sheeting on the ground. Work on a windless day.
3. Wet it down. Spray the sheets with water (using a garden sprayer, not a pressure jet) so that fibres do not rise into the air. Asbestos fibres can remain in the air of a work area for as long as 70–80 hours after the work.^[12]
4. Do not break or saw. Slate must not be broken, as this produces dust that is dangerous to health and the environment.^[11] Unscrew or carefully pull out the fixings, lift the sheets off whole and do not throw them to the ground. Do not use an angle grinder, saw or drill.
5. Take care on the roof. Old slate is brittle and must not be walked on, as you may fall through. Use boards or a ladder.
6. Pack it. Stack whole sheets on a pallet and wrap them in plastic film; put broken pieces into large bulk bags (“Big Bags”; about €7–8 per bag, 2023 figures).^[13] Store them separately from other building materials.
7. After the work. Put the overalls, gloves and filter into a bag together with the waste. Wash thoroughly. Do not take work clothes home, as fibres on clothing can endanger your family.^[14]

Where to dispose of it and what it costs

Slate is hazardous waste.^[15] It may only be delivered to landfills that hold a permit from the State Environmental Service (VVD).^[2] There it is disposed of in a separate cell.^[9]

• In 2024 the skiroviegli.lv website listed 18 acceptance points for asbestos-containing waste.^[8] An up-to-date map is available at skiroviegli.lv.
• Riga’s “Getliņi” landfill (2023 data) is not permitted to accept asbestos, so slate from the Riga region has to be taken to another region.^[13]
• In 2025 the hazardous waste operator “BAO” quoted a price of €550 per tonne excluding VAT, covering transport, temporary storage, repacking and disposal at a landfill.^[1] Prices vary, so compare several offers. 10 sheets weigh roughly 0.2 t.^[11]
• Before you set off, call the landfill to check whether it is currently accepting slate and how it must be packed.

State support for disposing of slate

What you must not do

• Bury slate in the ground or use it to fill in roads.^[2]
• Crush it and use it for a road surface or base, or for the paths between allotment beds.^[1][16]
• Throw it out with household waste or ordinary construction debris.^[1]
• Break or crush it: this creates hazardous dust.^[11]

Illegal handling of slate (for example, burying it or using it for road surfacing) can lead to a fine: €70–700 for individuals and €280–1,400 for legal entities (2025 figures), plus the cost of clearing it up.^[1] Buried slate wears down and crumbles over time, and asbestos can get into the soil, water and air.^[8]

Frequently asked questions