Roofing in Pakistan

Most roofs in Pakistan are flat. In cities they are mainly reinforced concrete slabs; in towns and villages they are commonly carried on steel girders or on timber and bamboo. The country's distinctive contributions to roofing history include some of the oldest planned cities in the world, in the Indus valley, and the windcatchers that once crowded the roofs of Hyderabad in Sindh.

Climate and hazards

Pakistan spans the hot, arid plains of Sindh and Punjab, where summer temperatures are among the highest in Asia, the monsoon-affected north-east, and the mountain ranges of the north and west with heavy winter snow. Earthquakes are a major hazard: the earthquake of 8 October 2005, of magnitude 7.6, killed more than 70,000 people. According to the World Bank, about two-thirds of the country's building stock is brick masonry and only 8% reinforced concrete, which makes buildings more vulnerable than in countries with similar seismic exposure.

Roofing history

The Indus civilisation's mature phase (about 2500-1900 BCE) produced cities such as Mohenjo-daro in Sindh, a UNESCO World Heritage Site built largely of brick in the 3rd millennium BCE, and Harappa in Punjab. Houses were of one or two storeys around courtyards, and many had stairs leading to upper courtyards or a second floor; how the roofs themselves were built is not preserved in the ruins.

In Hyderabad, rooftop windcatchers called mangh are said in some accounts to go back about 500 years; their decline is linked to the arrival of electricity in the 1920s. In the modern period steel joists ("girders" and "T-irons"), corrugated cement and iron sheets, and reinforced concrete came into wide use, as the census figures below show.

Traditional and vernacular roofs

• Timber and bamboo roofs: flat roofs carried on timber or bamboo members, the commonest rural type in the census categories.
• Girder and T-iron roofs: flat roofs carried on steel joists spanning between walls, recorded in the census as "girder/T-iron".
• Mangh windcatchers: fixed, triangular wind scoops on the roofs of Hyderabad and southern Sindh, facing the south-west sea breeze and fitted with rope-operated shutters.

The flat earth roofs of neighbouring Afghanistan (see Roofing in Afghanistan) are closely related.

Roofing today

The 2017 Population and Housing Census tabulated the roof material of owned housing units. In Sindh, which includes Karachi, the shares were:

Roof material	All Sindh	Rural	Urban
Wood/bamboo	35.7%	57.0%	9.6%
Girder/T-iron	33.0%	33.1%	32.8%
RCC/RBC (reinforced concrete or brick)	22.4%	3.0%	46.3%
Cement or iron sheet	6.9%	4.3%	10.1%
Other	2.1%	2.7%	1.3%

The figures show the typical pattern: concrete slabs dominate in cities, while rural houses are roofed with timber, bamboo or steel joists under earth. Corrugated cement and iron sheets are widely used for sheds, workshops and low-cost housing.

Codes, standards and regulation

The national seismic code is the Building Code of Pakistan (Seismic Provisions 2007), issued by the Ministry of Housing and Works; the Pakistan Engineering Council has since begun work on updating it. Enforcement is weak: local bylaws often do not follow the code.

Notable roofs

• Mohenjo-daro: Bronze Age brick city, a UNESCO World Heritage Site.
• Old Hyderabad, Sindh: known as Manghan jo Shahar, the "city of windcatchers".

Local roofing terms

• mangh (Sindhi): rooftop windcatcher; also badigar in southern Sindh
• wado sufo (Sindhi): main room ventilated by a mangh
• girder/T-iron: census term for roofs on steel joists

Sources and gaps

Detailed descriptions of how rural earth roofs in Pakistan are layered and maintained, national totals for roof materials and information on the domestic roofing industry were not found in published sources.