Alleged killer husband Brendan Banfield had special triple-glazed soundproof windows installed in his house to muffle the screams of his wife and a stranger while they were murdered, the jury at his trial in Virginia heard Thursday.

A window factory salesman testified that he had spoken with former IRS agent Banfield about the windows when they were installed, not long before he is alleged to have murdered Christine Banfield and Joseph Ryan at the house in a leafy Washington, DC, suburb.

He described them as “30% better in energy savings and noise level” in his testimony during the trial for Banfield, who is accused of masterminding a twisted double-murder rape plot so he could be with his Brazilian au pair, with whom he was having an 𝒶𝒻𝒻𝒶𝒾𝓇.

“When someone goes to a triple pane, that’s another level. And that is a type of level where they’re trying to do more than just protect the house from the sun,” the salesman added.

Christine Banfield, her husband Brendan Banfield, and their child, all smiling, with the child in a highchair wearing a "More Cake" bib.4

Brendan Banfield (left) is accused of killing his wife and another person — as part of a twisted rape plot to be with his Brazilian au pair, Juliana Peres Magalhaes.Christine Banfield/Instagram

Earlier this week, Banfield’s au pair, Peres Magalhaes, testified that the married father had the home’s windows replaced so neighbors wouldn’t hear screams during the murders.

Magalhaes, who earlier pleaded guilty to manslaughter for her role in the killings, claimed Banfield had her test out the windows by screaming to see if she could be heard from outside.

Banfield allegedly bought a gun from a shooting range in Northern Virginia a month before the murders, the jury was told.

Documents show he bought a Glock 43X pistol on Jan. 28, 2023. Amy Shotwell, an employee at Silver Eagle Group shooting range, testified that he had purchased the weapon that day.

Banfield has pleaded not guilty to murdering his wife and Ryan as part of a scheme to cover up his 𝒶𝒻𝒻𝒶𝒾𝓇 with his child’s nanny.

He and Magalhaes allegedly used photos of Christine to set up a 𝒻𝒶𝓀𝑒 profile on a fetish website, which they used to lure Ryan to the house to rape her, under the guise of a consensual BDSM 𝒔𝒆𝒙𝒖𝒂𝒍 encounter.

Banfield arriving at Fairfax County Circuit Court for his double murder trial on Jan. 14, 2026.

Banfield arriving at Fairfax County Circuit Court for his double murder trial on Jan. 14, 2026.AP Photo/Tom Brenner, Pool

Aerial view of a suburban house with police activity in the driveway, indicated by yellow and red 𝓉𝒶𝓅𝑒.

Banfield had special triple-glazed soundproof windows installed at his house to allegedly muffle the screams of his wife Christine and Joseph Ryan.ABC7 WJLA

Juliana Peres Magalhães testifying at Banfield's trial on Jan. 14, 2026.

Juliana Peres Magalhães testifying at Banfield’s trial on Jan. 14, 2026.AP Photo/Tom Brenner, Pool)

Earlier on Thursday, the jury heard that Magalhaes had moved her lingerie into the master bedroom just months after the killings.

Photographs of Banfield and his wife were also replaced with photos of him and Magalhaes between the date of the murders on Feb. 24, 2023, and October 2023, when the au pair was arrested.