M25 J6, J20, J3, J31 and at Junction 14 at Heathrow.
Around 20 protesters sat in the middle of the road in Kings Langley, causing tail backs up to the motorway, with some violence having already taken place.
They blocked the roundabout at junction 20 of the busy motorway, leading to outrage from drivers trying to use the road.
One driver is said to have left their car and attempted to grab a protester from the road and drag him away so they could continue their journey.
Other areas affected included junction three in Swanley, junction six in Godstone and junction 14 in Heathrow.
Police have since arrived to take control of the situation in Kings Langley, with around 50 officers reported to be gathering at the scene. There have been four arrests.
Essex Police have moved on the protesters at junction 31 and traffic restrictions were lifted. Some 11 arrests were made.
Junction three at Godstone has also reopened since the protect began.
Talking to LBC, a protester apologised for the problems they were causing, but said they had made the extreme move to get the government's attention.
Insulate Britain wants the government to "take responsibility for the insulation of all social housing in Britain" and create a "legally binding national plan to fully fund and take responsibility for the full low-energy and low-carbon whole-house retrofit", according to their site.
The group - which is relatively new and small - has warned that the motorway disruption is "just the start" of their demonstrations until the government decides to take action.
Two Kendal women are taking part in the protests. Gwen Harrison, 43, an environmental consultant said: "I am endlessly shocked at the lack of significant action from our government. They need to face up to reality.
"If don’t cut our use of fossil fuels urgently we will destroy our climate, our economy and the fabric of our society. They are being incredibly reckless.
"They are betting on technologies that don't exist. If we spend money now we’ll stop a catastrophe later down the line.
"It’s a no brainer. Insulating Britain will reduce emissions, provide hundreds of thousands of jobs and stop our elderly dying in cold homes each winter. "So stop messing about Boris and get on with the job!
"As soon as a statement is made that we can trust and is meaningful we will get off the roads."
Catherine Rennie Nash, 70, an events organiser and grandmother, said: "It's now proven that our use of fossil fuels has brought permanent change to our climate.
"The world I was born into has gone, and politicians are not doing enough to stop the damage. The world's politicians need to be honest.
"They need to act to protect our kids and grandchildren from a terrible future. We need real action from our government to reduce emissions this year - 2050 is far too late."
Surrey Police tweeted: "We're currently overseeing a protest at J6 M25 reported just before 8am. "Number of protesters from Insulate Britain are at the location, slip road closed and diversion being set up. "No arrests made at this stage. "Please avoid the area for the time being." Essex Police said: "We are currently dealing with an incident near junction 20 (Hemel Hempstead) of the M25 involving a small number of protesters. "Officers are at the scene. The M25 is currently closed at junction 20 westbound, and as a result there is heavy traffic on the A41. "Motorists are advised to avoid the area where possible." Former chief constable Sir Hugh Orde told LBC that peoples' right to protest is "proportionate", and for this particular demonstration "a clear message needs to be sent."
"It's worth reminding ourselves these people tried to stop a live motorway running, that is extraordinarily dangerous.
"It puts their lives at risk, it puts motorists' lives at risks and it puts police officers' lives at risk."