Adelaide-born squatter Craig Anthony Wheatman, 29, was jailed for at least nine years and three months on Thursday for the aggravated sexual assault in the Sydney woman's inner west home in January.

He admitted climbing through a bathroom window, flinging open the woman's bedroom door and making a threat while armed with garden shears.

The woman 64 years his senior couldn't understand his English beyond the words "cut" and "money".

"The victim must have been shocked and terrified by the presence of the offender who was unknown to her and in her bedroom at night," NSW District Court Judge Donna Woodburne said.

After "degrading sexual touching", the offender reached for an old plastic bag to place over his penis and raped the woman, repeatedly using his strength to overcome her attempts to move away, the judge said.

Wheatman ceased the rape but continued the crying woman's "rough and humiliating" treatment by ordering her into the bathroom and pouring cooking oil, Dettol and vinegar over her and her bedding.

He forced her to shower, temporarily keeping her in her shower seat under a stream of uncomfortably hot water.

Wheatman then collected her wallet, cordless phone, car keys and personal medical alarm, and abandoned the bruised, cut, swollen woman.

The medical alarm was activated about 2.10am, alerting the woman's family who arrived 90 minutes later.

Its GPS led police to a Burwood stormwater drain, where the other stolen items, covered in Wheatman's DNA, were found.

"But for the alarm being set off, it is not known how long she may have remained alone in an injured and shocked state," Judge Woodburne said.

The judge rejected any suggestion Wheatman's showering of the woman was an act of kindness. Rather, she said it was "selfish and demeaning conduct" borne of an appreciation the water would wash away evidence linking Wheatman to the crime.

"The victim and her family must have suffered terribly in trying to comprehend the harm done to the victim," the judge said.

Wheatman was arrested on January 24, telling police he'd been "paralytic drunk" and could only remember leaving the house knowing "I done something f***ing stupid".

"I just had the vibe, that feeling," he said.

Judge Woodburne accepted the offender's traumatic and dysfunctional childhood, including foster care and serious crimes by a primary caregiver, had caused antisocial and severe substance abuse disorders.

He'd aspired to be a DJ and guitarist but never held down a job.

In the two months before the rape, he was living an "isolated and chaotic existence", squatting in a derelict home in Loftus Crescent, Homebush, and mainly drinking or using illicit drugs.

Judge Woodburne imposed a total sentence of 14 years, backdating it to his arrest and noting a 25-per-cent discount for early guilty pleas to aggravated sexual assault and breaking and entering with intent to commit larceny.

She also took into account Wheatman's admissions to lesser offences committed during the rape.

Without the guilty pleas, the sentence for the rape alone would have been 16 years.

The court was not told of the victim's current condition.

Australian Associated Press