Among the ruin of Syria's long civil war are ghost villages of domed mudbrick homes found nowhere else on Earth.

Key points: Residents were forced to abandon their mudbrick homes due to conflict in Syria

Residents were forced to abandon their mudbrick homes due to conflict in Syria One builder has created a Syrian-style home in Lebanon using traditional mudbrick building techniques

One builder has created a Syrian-style home in Lebanon using traditional mudbrick building techniques An ethnologist is documenting the building process to create a manual for future generations

They're crumbling into dust, abandoned by residents who have fled the fighting.

Now, there's an effort to preserve the knowledge of how to build them before it is lost forever.

In Lebanon's Bekaa Valley, Syrian builder Issa el Khodr has carefully laid staggered tiers of mud bricks to create an elegant double-domed home.

Mr Issa built the structure from memory. ( ABC News: Adam Harvey )

It's almost certainly the first Syrian domed hut to be built in a decade, and there's a chance it could be the last of its kind ever to be built.

"In the past, I worked on houses with domes and I used my memory to build this house," Mr Issa said as he took a short break from working on the home made from 7,000 bricks of mud and straw.

This is how the people of northern Syria made their homes for centuries — put together with the only construction material at hand: the earth.

The domes help regulate the temperature and circulate air.

Mud walls are one metre thick — insulating against the fierce daytime heat and sub-zero winter nights.

The building techniques have been passed down through generations of families.

But many of those families have been forced out by the fighting in northern Syria, says Hoda Kassatly, an ethnologist from Lebanese NGO Arc en Ciel.

She's published a book of photographs about the villages.

Dr Kassatly toured the abandoned villages in April, with the empty homes disintegrating. ( ABC News: Adam Harvey )

"Last April, I went back to the same villages where I took the pictures," Dr Kassatly said.

"I realised that there were ghost villages, these villages have been emptied, they've become a military zone.

"Dwellers cannot come back and live there.

"These villages have disappeared."

That's not good for the people who lived there, of course, but the absence of the residents means the huts are disintegrating.

They need annual maintenance, like new layers of mud and straw on their outer walls to protect them against the harsh desert conditions.

The Syrian techniques were developed to insulate buildings from harsh heat and bitter cold. ( ABC News: Adam Harvey )

And with the families among the 13 million Syrians displaced across Syria and in neighbouring countries, Dr Kassatly says the knowledge of the ancient building techniques is vanishing just as quickly as the homes.

"At Arc en Ciel we realised that only a few builders still had this know-how," she said.

"With the war, we weren't able to find these builders anymore.

"We thought that it was urgent to preserve this precious architectural know-how."

Dr Kassatly is overseeing the construction of this hut, and is writing a crucial document — a manual on how to build others like it.

"After we start the construction and we publish a 'reproduction manual'," she said.

"Basically, this project should have taken place in Syria but because of the war we had to build it here in Lebanon.

The domes are built to regulate the temperature inside the homes. ( ABC News: Adam Harvey )

She's writing the manual on how it was built for when, or if, the villagers return.

"The manual will be distributed at a large scale to allow people to build again these houses," she said.

"The mud homes are difficult to build, and modern air conditioning means that it's a lot easier to live in a house made of thin concrete walls.

"It will be challenging to convince people to build again these kind of houses as they had already switched to concrete.

"Yet, it will be a matter of money because the ones who will go back to their village and can only use existing material … these people will use soil and will build their homes because they would need a shelter.

"There is a strong possibility that these people build again these kind of houses."

Mr Issa says these homes are important to Syrians.

"The person that has no past has no future," he said.

"We need to remember the past and how our ancestors lived, for the next generations.

"It's important that our children see how people were living."